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authorTakashi Iwai <tiwai@suse.de>2009-11-01 11:11:07 +0100
committerTakashi Iwai <tiwai@suse.de>2009-11-01 11:11:07 +0100
commite87a3dd33eab30b4db539500064a9584867e4f2c (patch)
tree2f7ad16e46ae30518ff63bb5391b63f7f7cc74dd /kernel
parentb14f5de731ae657d498d18d713c6431bfbeefb4b (diff)
parent3d00941371a765779c4e3509214c7e5793cce1fe (diff)
Merge branch 'fix/misc' into topic/misc
Diffstat (limited to 'kernel')
-rw-r--r--kernel/Makefile4
-rw-r--r--kernel/audit.c18
-rw-r--r--kernel/audit_watch.c2
-rw-r--r--kernel/auditsc.c6
-rw-r--r--kernel/cgroup.c1128
-rw-r--r--kernel/cgroup_debug.c105
-rw-r--r--kernel/cgroup_freezer.c15
-rw-r--r--kernel/cpuset.c66
-rw-r--r--kernel/cred.c19
-rw-r--r--kernel/exit.c164
-rw-r--r--kernel/fork.c75
-rw-r--r--kernel/futex.c137
-rw-r--r--kernel/gcov/Kconfig2
-rw-r--r--kernel/hrtimer.c93
-rw-r--r--kernel/hung_task.c4
-rw-r--r--kernel/itimer.c169
-rw-r--r--kernel/kallsyms.c3
-rw-r--r--kernel/kfifo.c2
-rw-r--r--kernel/kprobes.c6
-rw-r--r--kernel/lockdep.c3
-rw-r--r--kernel/lockdep_proc.c2
-rw-r--r--kernel/marker.c930
-rw-r--r--kernel/module.c184
-rw-r--r--kernel/ns_cgroup.c16
-rw-r--r--kernel/panic.c2
-rw-r--r--kernel/params.c7
-rw-r--r--kernel/perf_counter.c4963
-rw-r--r--kernel/perf_event.c5000
-rw-r--r--kernel/pid.c15
-rw-r--r--kernel/pid_namespace.c2
-rw-r--r--kernel/posix-cpu-timers.c155
-rw-r--r--kernel/power/console.c63
-rw-r--r--kernel/power/process.c1
-rw-r--r--kernel/power/snapshot.c2
-rw-r--r--kernel/power/swap.c1
-rw-r--r--kernel/printk.c27
-rw-r--r--kernel/profile.c45
-rw-r--r--kernel/ptrace.c11
-rw-r--r--kernel/rcupdate.c48
-rw-r--r--kernel/rcutorture.c43
-rw-r--r--kernel/rcutree.c105
-rw-r--r--kernel/rcutree.h2
-rw-r--r--kernel/rcutree_plugin.h110
-rw-r--r--kernel/rcutree_trace.c12
-rw-r--r--kernel/relay.c2
-rw-r--r--kernel/res_counter.c3
-rw-r--r--kernel/resource.c23
-rw-r--r--kernel/sched.c106
-rw-r--r--kernel/sched_clock.c122
-rw-r--r--kernel/sched_fair.c70
-rw-r--r--kernel/sched_idletask.c7
-rw-r--r--kernel/sched_rt.c13
-rw-r--r--kernel/signal.c168
-rw-r--r--kernel/slow-work.c12
-rw-r--r--kernel/smp.c36
-rw-r--r--kernel/softlockup.c4
-rw-r--r--kernel/sys.c46
-rw-r--r--kernel/sys_ni.c3
-rw-r--r--kernel/sysctl.c149
-rw-r--r--kernel/time/Makefile2
-rw-r--r--kernel/time/clocksource.c4
-rw-r--r--kernel/time/timeconv.c127
-rw-r--r--kernel/time/timer_list.c2
-rw-r--r--kernel/time/timer_stats.c2
-rw-r--r--kernel/timer.c36
-rw-r--r--kernel/trace/Kconfig2
-rw-r--r--kernel/trace/Makefile2
-rw-r--r--kernel/trace/blktrace.c39
-rw-r--r--kernel/trace/ftrace.c54
-rw-r--r--kernel/trace/power-traces.c20
-rw-r--r--kernel/trace/ring_buffer.c2
-rw-r--r--kernel/trace/trace.c70
-rw-r--r--kernel/trace/trace.h3
-rw-r--r--kernel/trace/trace_entries.h17
-rw-r--r--kernel/trace/trace_event_profile.c82
-rw-r--r--kernel/trace/trace_events.c56
-rw-r--r--kernel/trace/trace_hw_branches.c2
-rw-r--r--kernel/trace/trace_power.c218
-rw-r--r--kernel/trace/trace_printk.c1
-rw-r--r--kernel/trace/trace_stack.c4
-rw-r--r--kernel/trace/trace_syscalls.c99
-rw-r--r--kernel/tracepoint.c2
-rw-r--r--kernel/uid16.c1
-rw-r--r--kernel/utsname_sysctl.c4
84 files changed, 7705 insertions, 7677 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index 3d9c7e27e3f..b8d4cd8ac0b 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -58,7 +58,6 @@ obj-$(CONFIG_KEXEC) += kexec.o
obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
obj-$(CONFIG_COMPAT) += compat.o
obj-$(CONFIG_CGROUPS) += cgroup.o
-obj-$(CONFIG_CGROUP_DEBUG) += cgroup_debug.o
obj-$(CONFIG_CGROUP_FREEZER) += cgroup_freezer.o
obj-$(CONFIG_CPUSETS) += cpuset.o
obj-$(CONFIG_CGROUP_NS) += ns_cgroup.o
@@ -87,7 +86,6 @@ obj-$(CONFIG_RELAY) += relay.o
obj-$(CONFIG_SYSCTL) += utsname_sysctl.o
obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o
obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o
-obj-$(CONFIG_MARKERS) += marker.o
obj-$(CONFIG_TRACEPOINTS) += tracepoint.o
obj-$(CONFIG_LATENCYTOP) += latencytop.o
obj-$(CONFIG_FUNCTION_TRACER) += trace/
@@ -96,7 +94,7 @@ obj-$(CONFIG_X86_DS) += trace/
obj-$(CONFIG_RING_BUFFER) += trace/
obj-$(CONFIG_SMP) += sched_cpupri.o
obj-$(CONFIG_SLOW_WORK) += slow-work.o
-obj-$(CONFIG_PERF_COUNTERS) += perf_counter.o
+obj-$(CONFIG_PERF_EVENTS) += perf_event.o
ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER),y)
# According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is
diff --git a/kernel/audit.c b/kernel/audit.c
index defc2e6f1e3..5feed232be9 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -855,18 +855,24 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
break;
}
case AUDIT_SIGNAL_INFO:
- err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
- if (err)
- return err;
+ len = 0;
+ if (audit_sig_sid) {
+ err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
+ if (err)
+ return err;
+ }
sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
if (!sig_data) {
- security_release_secctx(ctx, len);
+ if (audit_sig_sid)
+ security_release_secctx(ctx, len);
return -ENOMEM;
}
sig_data->uid = audit_sig_uid;
sig_data->pid = audit_sig_pid;
- memcpy(sig_data->ctx, ctx, len);
- security_release_secctx(ctx, len);
+ if (audit_sig_sid) {
+ memcpy(sig_data->ctx, ctx, len);
+ security_release_secctx(ctx, len);
+ }
audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_SIGNAL_INFO,
0, 0, sig_data, sizeof(*sig_data) + len);
kfree(sig_data);
diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
index 0e96dbc60ea..cc7e87936cb 100644
--- a/kernel/audit_watch.c
+++ b/kernel/audit_watch.c
@@ -45,8 +45,8 @@
struct audit_watch {
atomic_t count; /* reference count */
- char *path; /* insertion path */
dev_t dev; /* associated superblock device */
+ char *path; /* insertion path */
unsigned long ino; /* associated inode number */
struct audit_parent *parent; /* associated parent */
struct list_head wlist; /* entry in parent->watches list */
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 68d3c6a0ecd..267e484f019 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -168,12 +168,12 @@ struct audit_context {
int in_syscall; /* 1 if task is in a syscall */
enum audit_state state, current_state;
unsigned int serial; /* serial number for record */
- struct timespec ctime; /* time of syscall entry */
int major; /* syscall number */
+ struct timespec ctime; /* time of syscall entry */
unsigned long argv[4]; /* syscall arguments */
- int return_valid; /* return code is valid */
long return_code;/* syscall return code */
u64 prio;
+ int return_valid; /* return code is valid */
int name_count;
struct audit_names names[AUDIT_NAMES];
char * filterkey; /* key for rule that triggered record */
@@ -198,8 +198,8 @@ struct audit_context {
char target_comm[TASK_COMM_LEN];
struct audit_tree_refs *trees, *first_trees;
- int tree_count;
struct list_head killed_trees;
+ int tree_count;
int type;
union {
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index c7ece8f027f..ca83b73fba1 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -23,6 +23,7 @@
*/
#include <linux/cgroup.h>
+#include <linux/ctype.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/kernel.h>
@@ -48,6 +49,8 @@
#include <linux/namei.h>
#include <linux/smp_lock.h>
#include <linux/pid_namespace.h>
+#include <linux/idr.h>
+#include <linux/vmalloc.h> /* TODO: replace with more sophisticated array */
#include <asm/atomic.h>
@@ -60,6 +63,8 @@ static struct cgroup_subsys *subsys[] = {
#include <linux/cgroup_subsys.h>
};
+#define MAX_CGROUP_ROOT_NAMELEN 64
+
/*
* A cgroupfs_root represents the root of a cgroup hierarchy,
* and may be associated with a superblock to form an active
@@ -74,6 +79,9 @@ struct cgroupfs_root {
*/
unsigned long subsys_bits;
+ /* Unique id for this hierarchy. */
+ int hierarchy_id;
+
/* The bitmask of subsystems currently attached to this hierarchy */
unsigned long actual_subsys_bits;
@@ -94,6 +102,9 @@ struct cgroupfs_root {
/* The path to use for release notifications. */
char release_agent_path[PATH_MAX];
+
+ /* The name for this hierarchy - may be empty */
+ char name[MAX_CGROUP_ROOT_NAMELEN];
};
/*
@@ -141,6 +152,10 @@ struct css_id {
static LIST_HEAD(roots);
static int root_count;
+static DEFINE_IDA(hierarchy_ida);
+static int next_hierarchy_id;
+static DEFINE_SPINLOCK(hierarchy_id_lock);
+
/* dummytop is a shorthand for the dummy hierarchy's top cgroup */
#define dummytop (&rootnode.top_cgroup)
@@ -201,6 +216,7 @@ struct cg_cgroup_link {
* cgroup, anchored on cgroup->css_sets
*/
struct list_head cgrp_link_list;
+ struct cgroup *cgrp;
/*
* List running through cg_cgroup_links pointing at a
* single css_set object, anchored on css_set->cg_links
@@ -227,8 +243,11 @@ static int cgroup_subsys_init_idr(struct cgroup_subsys *ss);
static DEFINE_RWLOCK(css_set_lock);
static int css_set_count;
-/* hash table for cgroup groups. This improves the performance to
- * find an existing css_set */
+/*
+ * hash table for cgroup groups. This improves the performance to find
+ * an existing css_set. This hash doesn't (currently) take into
+ * account cgroups in empty hierarchies.
+ */
#define CSS_SET_HASH_BITS 7
#define CSS_SET_TABLE_SIZE (1 << CSS_SET_HASH_BITS)
static struct hlist_head css_set_table[CSS_SET_TABLE_SIZE];
@@ -248,48 +267,22 @@ static struct hlist_head *css_set_hash(struct cgroup_subsys_state *css[])
return &css_set_table[index];
}
+static void free_css_set_rcu(struct rcu_head *obj)
+{
+ struct css_set *cg = container_of(obj, struct css_set, rcu_head);
+ kfree(cg);
+}
+
/* We don't maintain the lists running through each css_set to its
* task until after the first call to cgroup_iter_start(). This
* reduces the fork()/exit() overhead for people who have cgroups
* compiled into their kernel but not actually in use */
static int use_task_css_set_links __read_mostly;
-/* When we create or destroy a css_set, the operation simply
- * takes/releases a reference count on all the cgroups referenced
- * by subsystems in this css_set. This can end up multiple-counting
- * some cgroups, but that's OK - the ref-count is just a
- * busy/not-busy indicator; ensuring that we only count each cgroup
- * once would require taking a global lock to ensure that no
- * subsystems moved between hierarchies while we were doing so.
- *
- * Possible TODO: decide at boot time based on the number of
- * registered subsystems and the number of CPUs or NUMA nodes whether
- * it's better for performance to ref-count every subsystem, or to
- * take a global lock and only add one ref count to each hierarchy.
- */
-
-/*
- * unlink a css_set from the list and free it
- */
-static void unlink_css_set(struct css_set *cg)
+static void __put_css_set(struct css_set *cg, int taskexit)
{
struct cg_cgroup_link *link;
struct cg_cgroup_link *saved_link;
-
- hlist_del(&cg->hlist);
- css_set_count--;
-
- list_for_each_entry_safe(link, saved_link, &cg->cg_links,
- cg_link_list) {
- list_del(&link->cg_link_list);
- list_del(&link->cgrp_link_list);
- kfree(link);
- }
-}
-
-static void __put_css_set(struct css_set *cg, int taskexit)
-{
- int i;
/*
* Ensure that the refcount doesn't hit zero while any readers
* can see it. Similar to atomic_dec_and_lock(), but for an
@@ -302,21 +295,28 @@ static void __put_css_set(struct css_set *cg, int taskexit)
write_unlock(&css_set_lock);
return;
}
- unlink_css_set(cg);
- write_unlock(&css_set_lock);
- rcu_read_lock();
- for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
- struct cgroup *cgrp = rcu_dereference(cg->subsys[i]->cgroup);
+ /* This css_set is dead. unlink it and release cgroup refcounts */
+ hlist_del(&cg->hlist);
+ css_set_count--;
+
+ list_for_each_entry_safe(link, saved_link, &cg->cg_links,
+ cg_link_list) {
+ struct cgroup *cgrp = link->cgrp;
+ list_del(&link->cg_link_list);
+ list_del(&link->cgrp_link_list);
if (atomic_dec_and_test(&cgrp->count) &&
notify_on_release(cgrp)) {
if (taskexit)
set_bit(CGRP_RELEASABLE, &cgrp->flags);
check_for_release(cgrp);
}
+
+ kfree(link);
}
- rcu_read_unlock();
- kfree(cg);
+
+ write_unlock(&css_set_lock);
+ call_rcu(&cg->rcu_head, free_css_set_rcu);
}
/*
@@ -338,6 +338,78 @@ static inline void put_css_set_taskexit(struct css_set *cg)
}
/*
+ * compare_css_sets - helper function for find_existing_css_set().
+ * @cg: candidate css_set being tested
+ * @old_cg: existing css_set for a task
+ * @new_cgrp: cgroup that's being entered by the task
+ * @template: desired set of css pointers in css_set (pre-calculated)
+ *
+ * Returns true if "cg" matches "old_cg" except for the hierarchy
+ * which "new_cgrp" belongs to, for which it should match "new_cgrp".
+ */
+static bool compare_css_sets(struct css_set *cg,
+ struct css_set *old_cg,
+ struct cgroup *new_cgrp,
+ struct cgroup_subsys_state *template[])
+{
+ struct list_head *l1, *l2;
+
+ if (memcmp(template, cg->subsys, sizeof(cg->subsys))) {
+ /* Not all subsystems matched */
+ return false;
+ }
+
+ /*
+ * Compare cgroup pointers in order to distinguish between
+ * different cgroups in heirarchies with no subsystems. We
+ * could get by with just this check alone (and skip the
+ * memcmp above) but on most setups the memcmp check will
+ * avoid the need for this more expensive check on almost all
+ * candidates.
+ */
+
+ l1 = &cg->cg_links;
+ l2 = &old_cg->cg_links;
+ while (1) {
+ struct cg_cgroup_link *cgl1, *cgl2;
+ struct cgroup *cg1, *cg2;
+
+ l1 = l1->next;
+ l2 = l2->next;
+ /* See if we reached the end - both lists are equal length. */
+ if (l1 == &cg->cg_links) {
+ BUG_ON(l2 != &old_cg->cg_links);
+ break;
+ } else {
+ BUG_ON(l2 == &old_cg->cg_links);
+ }
+ /* Locate the cgroups associated with these links. */
+ cgl1 = list_entry(l1, struct cg_cgroup_link, cg_link_list);
+ cgl2 = list_entry(l2, struct cg_cgroup_link, cg_link_list);
+ cg1 = cgl1->cgrp;
+ cg2 = cgl2->cgrp;
+ /* Hierarchies should be linked in the same order. */
+ BUG_ON(cg1->root != cg2->root);
+
+ /*
+ * If this hierarchy is the hierarchy of the cgroup
+ * that's changing, then we need to check that this
+ * css_set points to the new cgroup; if it's any other
+ * hierarchy, then this css_set should point to the
+ * same cgroup as the old css_set.
+ */
+ if (cg1->root == new_cgrp->root) {
+ if (cg1 != new_cgrp)
+ return false;
+ } else {
+ if (cg1 != cg2)
+ return false;
+ }
+ }
+ return true;
+}
+
+/*
* find_existing_css_set() is a helper for
* find_css_set(), and checks to see whether an existing
* css_set is suitable.
@@ -378,10 +450,11 @@ static struct css_set *find_existing_css_set(
hhead = css_set_hash(template);
hlist_for_each_entry(cg, node, hhead, hlist) {
- if (!memcmp(template, cg->subsys, sizeof(cg->subsys))) {
- /* All subsystems matched */
- return cg;
- }
+ if (!compare_css_sets(cg, oldcg, cgrp, template))
+ continue;
+
+ /* This css_set matches what we need */
+ return cg;
}
/* No existing cgroup group matched */
@@ -435,8 +508,14 @@ static void link_css_set(struct list_head *tmp_cg_links,
link = list_first_entry(tmp_cg_links, struct cg_cgroup_link,
cgrp_link_list);
link->cg = cg;
+ link->cgrp = cgrp;
+ atomic_inc(&cgrp->count);
list_move(&link->cgrp_link_list, &cgrp->css_sets);
- list_add(&link->cg_link_list, &cg->cg_links);
+ /*
+ * Always add links to the tail of the list so that the list
+ * is sorted by order of hierarchy creation
+ */
+ list_add_tail(&link->cg_link_list, &cg->cg_links);
}
/*
@@ -451,11 +530,11 @@ static struct css_set *find_css_set(
{
struct css_set *res;
struct cgroup_subsys_state *template[CGROUP_SUBSYS_COUNT];
- int i;
struct list_head tmp_cg_links;
struct hlist_head *hhead;
+ struct cg_cgroup_link *link;
/* First see if we already have a cgroup group that matches
* the desired set */
@@ -489,20 +568,12 @@ static struct css_set *find_css_set(
write_lock(&css_set_lock);
/* Add reference counts and links from the new css_set. */
- for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
- struct cgroup *cgrp = res->subsys[i]->cgroup;
- struct cgroup_subsys *ss = subsys[i];
- atomic_inc(&cgrp->count);
- /*
- * We want to add a link once per cgroup, so we
- * only do it for the first subsystem in each
- * hierarchy
- */
- if (ss->root->subsys_list.next == &ss->sibling)
- link_css_set(&tmp_cg_links, res, cgrp);
+ list_for_each_entry(link, &oldcg->cg_links, cg_link_list) {
+ struct cgroup *c = link->cgrp;
+ if (c->root == cgrp->root)
+ c = cgrp;
+ link_css_set(&tmp_cg_links, res, c);
}
- if (list_empty(&rootnode.subsys_list))
- link_css_set(&tmp_cg_links, res, dummytop);
BUG_ON(!list_empty(&tmp_cg_links));
@@ -518,6 +589,41 @@ static struct css_set *find_css_set(
}
/*
+ * Return the cgroup for "task" from the given hierarchy. Must be
+ * called with cgroup_mutex held.
+ */
+static struct cgroup *task_cgroup_from_root(struct task_struct *task,
+ struct cgroupfs_root *root)
+{
+ struct css_set *css;
+ struct cgroup *res = NULL;
+
+ BUG_ON(!mutex_is_locked(&cgroup_mutex));
+ read_lock(&css_set_lock);
+ /*
+ * No need to lock the task - since we hold cgroup_mutex the
+ * task can't change groups, so the only thing that can happen
+ * is that it exits and its css is set back to init_css_set.
+ */
+ css = task->cgroups;
+ if (css == &init_css_set) {
+ res = &root->top_cgroup;
+ } else {
+ struct cg_cgroup_link *link;
+ list_for_each_entry(link, &css->cg_links, cg_link_list) {
+ struct cgroup *c = link->cgrp;
+ if (c->root == root) {
+ res = c;
+ break;
+ }
+ }
+ }
+ read_unlock(&css_set_lock);
+ BUG_ON(!res);
+ return res;
+}
+
+/*
* There is one global cgroup mutex. We also require taking
* task_lock() when dereferencing a task's cgroup subsys pointers.
* See "The task_lock() exception", at the end of this comment.
@@ -596,8 +702,8 @@ void cgroup_unlock(void)
static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, int mode);
static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry);
static int cgroup_populate_dir(struct cgroup *cgrp);
-static struct inode_operations cgroup_dir_inode_operations;
-static struct file_operations proc_cgroupstats_operations;
+static const struct inode_operations cgroup_dir_inode_operations;
+static const struct file_operations proc_cgroupstats_operations;
static struct backing_dev_info cgroup_backing_dev_info = {
.name = "cgroup",
@@ -677,6 +783,12 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode)
*/
deactivate_super(cgrp->root->sb);
+ /*
+ * if we're getting rid of the cgroup, refcount should ensure
+ * that there are no pidlists left.
+ */
+ BUG_ON(!list_empty(&cgrp->pidlists));
+
call_rcu(&cgrp->rcu_head, free_cgroup_rcu);
}
iput(inode);
@@ -841,6 +953,8 @@ static int cgroup_show_options(struct seq_file *seq, struct vfsmount *vfs)
seq_puts(seq, ",noprefix");
if (strlen(root->release_agent_path))
seq_printf(seq, ",release_agent=%s", root->release_agent_path);
+ if (strlen(root->name))
+ seq_printf(seq, ",name=%s", root->name);
mutex_unlock(&cgroup_mutex);
return 0;
}
@@ -849,6 +963,12 @@ struct cgroup_sb_opts {
unsigned long subsys_bits;
unsigned long flags;
char *release_agent;
+ char *name;
+ /* User explicitly requested empty subsystem */
+ bool none;
+
+ struct cgroupfs_root *new_root;
+
};
/* Convert a hierarchy specifier into a bitmask of subsystems and
@@ -863,9 +983,7 @@ static int parse_cgroupfs_options(char *data,
mask = ~(1UL << cpuset_subsys_id);
#endif
- opts->subsys_bits = 0;
- opts->flags = 0;
- opts->release_agent = NULL;
+ memset(opts, 0, sizeof(*opts));
while ((token = strsep(&o, ",")) != NULL) {
if (!*token)
@@ -879,17 +997,42 @@ static int parse_cgroupfs_options(char *data,
if (!ss->disabled)
opts->subsys_bits |= 1ul << i;
}
+ } else if (!strcmp(token, "none")) {
+ /* Explicitly have no subsystems */
+ opts->none = true;
} else if (!strcmp(token, "noprefix")) {
set_bit(ROOT_NOPREFIX, &opts->flags);
} else if (!strncmp(token, "release_agent=", 14)) {
/* Specifying two release agents is forbidden */
if (opts->release_agent)
return -EINVAL;
- opts->release_agent = kzalloc(PATH_MAX, GFP_KERNEL);
+ opts->release_agent =
+ kstrndup(token + 14, PATH_MAX, GFP_KERNEL);
if (!opts->release_agent)
return -ENOMEM;
- strncpy(opts->release_agent, token + 14, PATH_MAX - 1);
- opts->release_agent[PATH_MAX - 1] = 0;
+ } else if (!strncmp(token, "name=", 5)) {
+ int i;
+ const char *name = token + 5;
+ /* Can't specify an empty name */
+ if (!strlen(name))
+ return -EINVAL;
+ /* Must match [\w.-]+ */
+ for (i = 0; i < strlen(name); i++) {
+ char c = name[i];
+ if (isalnum(c))
+ continue;
+ if ((c == '.') || (c == '-') || (c == '_'))
+ continue;
+ return -EINVAL;
+ }
+ /* Specifying two names is forbidden */
+ if (opts->name)
+ return -EINVAL;
+ opts->name = kstrndup(name,
+ MAX_CGROUP_ROOT_NAMELEN,
+ GFP_KERNEL);
+ if (!opts->name)
+ return -ENOMEM;
} else {
struct cgroup_subsys *ss;
int i;
@@ -906,6 +1049,8 @@ static int parse_cgroupfs_options(char *data,
}
}
+ /* Consistency checks */
+
/*
* Option noprefix was introduced just for backward compatibility
* with the old cpuset, so we allow noprefix only if mounting just
@@ -915,8 +1060,16 @@ static int parse_cgroupfs_options(char *data,
(opts->subsys_bits & mask))
return -EINVAL;
- /* We can't have an empty hierarchy */
- if (!opts->subsys_bits)
+
+ /* Can't specify "none" and some subsystems */
+ if (opts->subsys_bits && opts->none)
+ return -EINVAL;
+
+ /*
+ * We either have to specify by name or by subsystems. (So all
+ * empty hierarchies must have a name).
+ */
+ if (!opts->subsys_bits && !opts->name)
return -EINVAL;
return 0;
@@ -944,6 +1097,12 @@ static int cgroup_remount(struct super_block *sb, int *flags, char *data)
goto out_unlock;
}
+ /* Don't allow name to change at remount */
+ if (opts.name && strcmp(opts.name, root->name)) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
ret = rebind_subsystems(root, opts.subsys_bits);
if (ret)
goto out_unlock;
@@ -955,13 +1114,14 @@ static int cgroup_remount(struct super_block *sb, int *flags, char *data)
strcpy(root->release_agent_path, opts.release_agent);
out_unlock:
kfree(opts.release_agent);
+ kfree(opts.name);
mutex_unlock(&cgroup_mutex);
mutex_unlock(&cgrp->dentry->d_inode->i_mutex);
unlock_kernel();
return ret;
}
-static struct super_operations cgroup_ops = {
+static const struct super_operations cgroup_ops = {
.statfs = simple_statfs,
.drop_inode = generic_delete_inode,
.show_options = cgroup_show_options,
@@ -974,9 +1134,10 @@ static void init_cgroup_housekeeping(struct cgroup *cgrp)
INIT_LIST_HEAD(&cgrp->children);
INIT_LIST_HEAD(&cgrp->css_sets);
INIT_LIST_HEAD(&cgrp->release_list);
- INIT_LIST_HEAD(&cgrp->pids_list);
- init_rwsem(&cgrp->pids_mutex);
+ INIT_LIST_HEAD(&cgrp->pidlists);
+ mutex_init(&cgrp->pidlist_mutex);
}
+
static void init_cgroup_root(struct cgroupfs_root *root)
{
struct cgroup *cgrp = &root->top_cgroup;
@@ -988,33 +1149,106 @@ static void init_cgroup_root(struct cgroupfs_root *root)
init_cgroup_housekeeping(cgrp);
}
+static bool init_root_id(struct cgroupfs_root *root)
+{
+ int ret = 0;
+
+ do {
+ if (!ida_pre_get(&hierarchy_ida, GFP_KERNEL))
+ return false;
+ spin_lock(&hierarchy_id_lock);
+ /* Try to allocate the next unused ID */
+ ret = ida_get_new_above(&hierarchy_ida, next_hierarchy_id,
+ &root->hierarchy_id);
+ if (ret == -ENOSPC)
+ /* Try again starting from 0 */
+ ret = ida_get_new(&hierarchy_ida, &root->hierarchy_id);
+ if (!ret) {
+ next_hierarchy_id = root->hierarchy_id + 1;
+ } else if (ret != -EAGAIN) {
+ /* Can only get here if the 31-bit IDR is full ... */
+ BUG_ON(ret);
+ }
+ spin_unlock(&hierarchy_id_lock);
+ } while (ret);
+ return true;
+}
+
static int cgroup_test_super(struct super_block *sb, void *data)
{
- struct cgroupfs_root *new = data;
+ struct cgroup_sb_opts *opts = data;
struct cgroupfs_root *root = sb->s_fs_info;
- /* First check subsystems */
- if (new->subsys_bits != root->subsys_bits)
- return 0;
+ /* If we asked for a name then it must match */
+ if (opts->name && strcmp(opts->name, root->name))
+ return 0;
- /* Next check flags */
- if (new->flags != root->flags)
+ /*
+ * If we asked for subsystems (or explicitly for no
+ * subsystems) then they must match
+ */
+ if ((opts->subsys_bits || opts->none)
+ && (opts->subsys_bits != root->subsys_bits))
return 0;
return 1;
}
+static struct cgroupfs_root *cgroup_root_from_opts(struct cgroup_sb_opts *opts)
+{
+ struct cgroupfs_root *root;
+
+ if (!opts->subsys_bits && !opts->none)
+ return NULL;
+
+ root = kzalloc(sizeof(*root), GFP_KERNEL);
+ if (!root)
+ return ERR_PTR(-ENOMEM);
+
+ if (!init_root_id(root)) {
+ kfree(root);
+ return ERR_PTR(-ENOMEM);
+ }
+ init_cgroup_root(root);
+
+ root->subsys_bits = opts->subsys_bits;
+ root->flags = opts->flags;
+ if (opts->release_agent)
+ strcpy(root->release_agent_path, opts->release_agent);
+ if (opts->name)
+ strcpy(root->name, opts->name);
+ return root;
+}
+
+static void cgroup_drop_root(struct cgroupfs_root *root)
+{
+ if (!root)
+ return;
+
+ BUG_ON(!root->hierarchy_id);
+ spin_lock(&hierarchy_id_lock);
+ ida_remove(&hierarchy_ida, root->hierarchy_id);
+ spin_unlock(&hierarchy_id_lock);
+ kfree(root);
+}
+
static int cgroup_set_super(struct super_block *sb, void *data)
{
int ret;
- struct cgroupfs_root *root = data;
+ struct cgroup_sb_opts *opts = data;
+
+ /* If we don't have a new root, we can't set up a new sb */
+ if (!opts->new_root)
+ return -EINVAL;
+
+ BUG_ON(!opts->subsys_bits && !opts->none);
ret = set_anon_super(sb, NULL);
if (ret)
return ret;
- sb->s_fs_info = root;
- root->sb = sb;
+ sb->s_fs_info = opts->new_root;
+ opts->new_root->sb = sb;
sb->s_blocksize = PAGE_CACHE_SIZE;
sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
@@ -1051,48 +1285,43 @@ static int cgroup_get_sb(struct file_system_type *fs_type,
void *data, struct vfsmount *mnt)
{
struct cgroup_sb_opts opts;
+ struct cgroupfs_root *root;
int ret = 0;
struct super_block *sb;
- struct cgroupfs_root *root;
- struct list_head tmp_cg_links;
+ struct cgroupfs_root *new_root;
/* First find the desired set of subsystems */
ret = parse_cgroupfs_options(data, &opts);
- if (ret) {
- kfree(opts.release_agent);
- return ret;
- }
-
- root = kzalloc(sizeof(*root), GFP_KERNEL);
- if (!root) {
- kfree(opts.release_agent);
- return -ENOMEM;
- }
+ if (ret)
+ goto out_err;
- init_cgroup_root(root);
- root->subsys_bits = opts.subsys_bits;
- root->flags = opts.flags;
- if (opts.release_agent) {
- strcpy(root->release_agent_path, opts.release_agent);
- kfree(opts.release_agent);
+ /*
+ * Allocate a new cgroup root. We may not need it if we're
+ * reusing an existing hierarchy.
+ */
+ new_root = cgroup_root_from_opts(&opts);
+ if (IS_ERR(new_root)) {
+ ret = PTR_ERR(new_root);
+ goto out_err;
}
+ opts.new_root = new_root;
- sb = sget(fs_type, cgroup_test_super, cgroup_set_super, root);
-
+ /* Locate an existing or new sb for this hierarchy */
+ sb = sget(fs_type, cgroup_test_super, cgroup_set_super, &opts);
if (IS_ERR(sb)) {
- kfree(root);
- return PTR_ERR(sb);
+ ret = PTR_ERR(sb);
+ cgroup_drop_root(opts.new_root);
+ goto out_err;
}
- if (sb->s_fs_info != root) {
- /* Reusing an existing superblock */
- BUG_ON(sb->s_root == NULL);
- kfree(root);
- root = NULL;
- } else {
- /* New superblock */
+ root = sb->s_fs_info;
+ BUG_ON(!root);
+ if (root == opts.new_root) {
+ /* We used the new root structure, so this is a new hierarchy */
+ struct list_head tmp_cg_links;
struct cgroup *root_cgrp = &root->top_cgroup;
struct inode *inode;
+ struct cgroupfs_root *existing_root;
int i;
BUG_ON(sb->s_root != NULL);
@@ -1105,6 +1334,18 @@ static int cgroup_get_sb(struct file_system_type *fs_type,
mutex_lock(&inode->i_mutex);
mutex_lock(&cgroup_mutex);
+ if (strlen(root->name)) {
+ /* Check for name clashes with existing mounts */
+ for_each_active_root(existing_root) {
+ if (!strcmp(existing_root->name, root->name)) {
+ ret = -EBUSY;
+ mutex_unlock(&cgroup_mutex);
+ mutex_unlock(&inode->i_mutex);
+ goto drop_new_super;
+ }
+ }
+ }
+
/*
* We're accessing css_set_count without locking
* css_set_lock here, but that's OK - it can only be
@@ -1123,7 +1364,8 @@ static int cgroup_get_sb(struct file_system_type *fs_type,
if (ret == -EBUSY) {
mutex_unlock(&cgroup_mutex);
mutex_unlock(&inode->i_mutex);
- goto free_cg_links;
+ free_cg_links(&tmp_cg_links);
+ goto drop_new_super;
}
/* EBUSY should be the only error here */
@@ -1155,17 +1397,27 @@ static int cgroup_get_sb(struct file_system_type *fs_type,
BUG_ON(root->number_of_cgroups != 1);
cgroup_populate_dir(root_cgrp);
- mutex_unlock(&inode->i_mutex);
mutex_unlock(&cgroup_mutex);
+ mutex_unlock(&inode->i_mutex);
+ } else {
+ /*
+ * We re-used an existing hierarchy - the new root (if
+ * any) is not needed
+ */
+ cgroup_drop_root(opts.new_root);
}
simple_set_mnt(mnt, sb);
+ kfree(opts.release_agent);
+ kfree(opts.name);
return 0;
- free_cg_links:
- free_cg_links(&tmp_cg_links);
drop_new_super:
deactivate_locked_super(sb);
+ out_err:
+ kfree(opts.release_agent);
+ kfree(opts.name);
+
return ret;
}
@@ -1211,7 +1463,7 @@ static void cgroup_kill_sb(struct super_block *sb) {
mutex_unlock(&cgroup_mutex);
kill_litter_super(sb);
- kfree(root);
+ cgroup_drop_root(root);
}
static struct file_system_type cgroup_fs_type = {
@@ -1276,27 +1528,6 @@ int cgroup_path(const struct cgroup *cgrp, char *buf, int buflen)
return 0;
}
-/*
- * Return the first subsystem attached to a cgroup's hierarchy, and
- * its subsystem id.
- */
-
-static void get_first_subsys(const struct cgroup *cgrp,
- struct cgroup_subsys_state **css, int *subsys_id)
-{
- const struct cgroupfs_root *root = cgrp->root;
- const struct cgroup_subsys *test_ss;
- BUG_ON(list_empty(&root->subsys_list));
- test_ss = list_entry(root->subsys_list.next,
- struct cgroup_subsys, sibling);
- if (css) {
- *css = cgrp->subsys[test_ss->subsys_id];
- BUG_ON(!*css);
- }
- if (subsys_id)
- *subsys_id = test_ss->subsys_id;
-}
-
/**
* cgroup_attach_task - attach task 'tsk' to cgroup 'cgrp'
* @cgrp: the cgroup the task is attaching to
@@ -1313,18 +1544,15 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
struct css_set *cg;
struct css_set *newcg;
struct cgroupfs_root *root = cgrp->root;
- int subsys_id;
-
- get_first_subsys(cgrp, NULL, &subsys_id);
/* Nothing to do if the task is already in that cgroup */
- oldcgrp = task_cgroup(tsk, subsys_id);
+ oldcgrp = task_cgroup_from_root(tsk, root);
if (cgrp == oldcgrp)
return 0;
for_each_subsys(root, ss) {
if (ss->can_attach) {
- retval = ss->can_attach(ss, cgrp, tsk);
+ retval = ss->can_attach(ss, cgrp, tsk, false);
if (retval)
return retval;
}
@@ -1362,7 +1590,7 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
for_each_subsys(root, ss) {
if (ss->attach)
- ss->attach(ss, cgrp, oldcgrp, tsk);
+ ss->attach(ss, cgrp, oldcgrp, tsk, false);
}
set_bit(CGRP_RELEASABLE, &oldcgrp->flags);
synchronize_rcu();
@@ -1423,15 +1651,6 @@ static int cgroup_tasks_write(struct cgroup *cgrp, struct cftype *cft, u64 pid)
return ret;
}
-/* The various types of files and directories in a cgroup file system */
-enum cgroup_filetype {
- FILE_ROOT,
- FILE_DIR,
- FILE_TASKLIST,
- FILE_NOTIFY_ON_RELEASE,
- FILE_RELEASE_AGENT,
-};
-
/**
* cgroup_lock_live_group - take cgroup_mutex and check that cgrp is alive.
* @cgrp: the cgroup to be checked for liveness
@@ -1644,7 +1863,7 @@ static int cgroup_seqfile_release(struct inode *inode, struct file *file)
return single_release(inode, file);
}
-static struct file_operations cgroup_seqfile_operations = {
+static const struct file_operations cgroup_seqfile_operations = {
.read = seq_read,
.write = cgroup_file_write,
.llseek = seq_lseek,
@@ -1703,7 +1922,7 @@ static int cgroup_rename(struct inode *old_dir, struct dentry *old_dentry,
return simple_rename(old_dir, old_dentry, new_dir, new_dentry);
}
-static struct file_operations cgroup_file_operations = {
+static const struct file_operations cgroup_file_operations = {
.read = cgroup_file_read,
.write = cgroup_file_write,
.llseek = generic_file_llseek,
@@ -1711,7 +1930,7 @@ static struct file_operations cgroup_file_operations = {
.release = cgroup_file_release,
};
-static struct inode_operations cgroup_dir_inode_operations = {
+static const struct inode_operations cgroup_dir_inode_operations = {
.lookup = simple_lookup,
.mkdir = cgroup_mkdir,
.rmdir = cgroup_rmdir,
@@ -1876,7 +2095,7 @@ int cgroup_task_count(const struct cgroup *cgrp)
* the start of a css_set
*/
static void cgroup_advance_iter(struct cgroup *cgrp,
- struct cgroup_iter *it)
+ struct cgroup_iter *it)
{
struct list_head *l = it->cg_link;
struct cg_cgroup_link *link;
@@ -2129,7 +2348,7 @@ int cgroup_scan_tasks(struct cgroup_scanner *scan)
}
/*
- * Stuff for reading the 'tasks' file.
+ * Stuff for reading the 'tasks'/'procs' files.
*
* Reading this file can return large amounts of data if a cgroup has
* *lots* of attached tasks. So it may need several calls to read(),
@@ -2139,27 +2358,196 @@ int cgroup_scan_tasks(struct cgroup_scanner *scan)
*/
/*
- * Load into 'pidarray' up to 'npids' of the tasks using cgroup
- * 'cgrp'. Return actual number of pids loaded. No need to
- * task_lock(p) when reading out p->cgroup, since we're in an RCU
- * read section, so the css_set can't go away, and is
- * immutable after creation.
+ * The following two functions "fix" the issue where there are more pids
+ * than kmalloc will give memory for; in such cases, we use vmalloc/vfree.
+ * TODO: replace with a kernel-wide solution to this problem
+ */
+#define PIDLIST_TOO_LARGE(c) ((c) * sizeof(pid_t) > (PAGE_SIZE * 2))
+static void *pidlist_allocate(int count)
+{
+ if (PIDLIST_TOO_LARGE(count))
+ return vmalloc(count * sizeof(pid_t));
+ else
+ return kmalloc(count * sizeof(pid_t), GFP_KERNEL);
+}
+static void pidlist_free(void *p)
+{
+ if (is_vmalloc_addr(p))
+ vfree(p);
+ else
+ kfree(p);
+}
+static void *pidlist_resize(void *p, int newcount)
+{
+ void *newlist;
+ /* note: if new alloc fails, old p will still be valid either way */
+ if (is_vmalloc_addr(p)) {
+ newlist = vmalloc(newcount * sizeof(pid_t));
+ if (!newlist)
+ return NULL;
+ memcpy(newlist, p, newcount * sizeof(pid_t));
+ vfree(p);
+ } else {
+ newlist = krealloc(p, newcount * sizeof(pid_t), GFP_KERNEL);
+ }
+ return newlist;
+}
+
+/*
+ * pidlist_uniq - given a kmalloc()ed list, strip out all duplicate entries
+ * If the new stripped list is sufficiently smaller and there's enough memory
+ * to allocate a new buffer, will let go of the unneeded memory. Returns the
+ * number of unique elements.
+ */
+/* is the size difference enough that we should re-allocate the array? */
+#define PIDLIST_REALLOC_DIFFERENCE(old, new) ((old) - PAGE_SIZE >= (new))
+static int pidlist_uniq(pid_t **p, int length)
+{
+ int src, dest = 1;
+ pid_t *list = *p;
+ pid_t *newlist;
+
+ /*
+ * we presume the 0th element is unique, so i starts at 1. trivial
+ * edge cases first; no work needs to be done for either
+ */
+ if (length == 0 || length == 1)
+ return length;
+ /* src and dest walk down the list; dest counts unique elements */
+ for (src = 1; src < length; src++) {
+ /* find next unique element */
+ while (list[src] == list[src-1]) {
+ src++;
+ if (src == length)
+ goto after;
+ }
+ /* dest always points to where the next unique element goes */
+ list[dest] = list[src];
+ dest++;
+ }
+after:
+ /*
+ * if the length difference is large enough, we want to allocate a
+ * smaller buffer to save memory. if this fails due to out of memory,
+ * we'll just stay with what we've got.
+ */
+ if (PIDLIST_REALLOC_DIFFERENCE(length, dest)) {
+ newlist = pidlist_resize(list, dest);
+ if (newlist)
+ *p = newlist;
+ }
+ return dest;
+}
+
+static int cmppid(const void *a, const void *b)
+{
+ return *(pid_t *)a - *(pid_t *)b;
+}
+
+/*
+ * find the appropriate pidlist for our purpose (given procs vs tasks)
+ * returns with the lock on that pidlist already held, and takes care
+ * of the use count, or returns NULL with no locks held if we're out of
+ * memory.
*/
-static int pid_array_load(pid_t *pidarray, int npids, struct cgroup *cgrp)
+static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp,
+ enum cgroup_filetype type)
{
- int n = 0, pid;
+ struct cgroup_pidlist *l;
+ /* don't need task_nsproxy() if we're looking at ourself */
+ struct pid_namespace *ns = get_pid_ns(current->nsproxy->pid_ns);
+ /*
+ * We can't drop the pidlist_mutex before taking the l->mutex in case
+ * the last ref-holder is trying to remove l from the list at the same
+ * time. Holding the pidlist_mutex precludes somebody taking whichever
+ * list we find out from under us - compare release_pid_array().
+ */
+ mutex_lock(&cgrp->pidlist_mutex);
+ list_for_each_entry(l, &cgrp->pidlists, links) {
+ if (l->key.type == type && l->key.ns == ns) {
+ /* found a matching list - drop the extra refcount */
+ put_pid_ns(ns);
+ /* make sure l doesn't vanish out from under us */
+ down_write(&l->mutex);
+ mutex_unlock(&cgrp->pidlist_mutex);
+ l->use_count++;
+ return l;
+ }
+ }
+ /* entry not found; create a new one */
+ l = kmalloc(sizeof(struct cgroup_pidlist), GFP_KERNEL);
+ if (!l) {
+ mutex_unlock(&cgrp->pidlist_mutex);
+ put_pid_ns(ns);
+ return l;
+ }
+ init_rwsem(&l->mutex);
+ down_write(&l->mutex);
+ l->key.type = type;
+ l->key.ns = ns;
+ l->use_count = 0; /* don't increment here */
+ l->list = NULL;
+ l->owner = cgrp;
+ list_add(&l->links, &cgrp->pidlists);
+ mutex_unlock(&cgrp->pidlist_mutex);
+ return l;
+}
+
+/*
+ * Load a cgroup's pidarray with either procs' tgids or tasks' pids
+ */
+static int pidlist_array_load(struct cgroup *cgrp, enum cgroup_filetype type,
+ struct cgroup_pidlist **lp)
+{
+ pid_t *array;
+ int length;
+ int pid, n = 0; /* used for populating the array */
struct cgroup_iter it;
struct task_struct *tsk;
+ struct cgroup_pidlist *l;
+
+ /*
+ * If cgroup gets more users after we read count, we won't have
+ * enough space - tough. This race is indistinguishable to the
+ * caller from the case that the additional cgroup users didn't
+ * show up until sometime later on.
+ */
+ length = cgroup_task_count(cgrp);
+ array = pidlist_allocate(length);
+ if (!array)
+ return -ENOMEM;
+ /* now, populate the array */
cgroup_iter_start(cgrp, &it);
while ((tsk = cgroup_iter_next(cgrp, &it))) {
- if (unlikely(n == npids))
+ if (unlikely(n == length))
break;
- pid = task_pid_vnr(tsk);
- if (pid > 0)
- pidarray[n++] = pid;
+ /* get tgid or pid for procs or tasks file respectively */
+ if (type == CGROUP_FILE_PROCS)
+ pid = task_tgid_vnr(tsk);
+ else
+ pid = task_pid_vnr(tsk);
+ if (pid > 0) /* make sure to only use valid results */
+ array[n++] = pid;
}
cgroup_iter_end(cgrp, &it);
- return n;
+ length = n;
+ /* now sort & (if procs) strip out duplicates */
+ sort(array, length, sizeof(pid_t), cmppid, NULL);
+ if (type == CGROUP_FILE_PROCS)
+ length = pidlist_uniq(&array, length);
+ l = cgroup_pidlist_find(cgrp, type);
+ if (!l) {
+ pidlist_free(array);
+ return -ENOMEM;
+ }
+ /* store array, freeing old if necessary - lock already held */
+ pidlist_free(l->list);
+ l->list = array;
+ l->length = length;
+ l->use_count++;
+ up_write(&l->mutex);
+ *lp = l;
+ return 0;
}
/**
@@ -2216,37 +2604,14 @@ err:
return ret;
}
-/*
- * Cache pids for all threads in the same pid namespace that are
- * opening the same "tasks" file.
- */
-struct cgroup_pids {
- /* The node in cgrp->pids_list */
- struct list_head list;
- /* The cgroup those pids belong to */
- struct cgroup *cgrp;
- /* The namepsace those pids belong to */
- struct pid_namespace *ns;
- /* Array of process ids in the cgroup */
- pid_t *tasks_pids;
- /* How many files are using the this tasks_pids array */
- int use_count;
- /* Length of the current tasks_pids array */
- int length;
-};
-
-static int cmppid(const void *a, const void *b)
-{
- return *(pid_t *)a - *(pid_t *)b;
-}
/*
- * seq_file methods for the "tasks" file. The seq_file position is the
+ * seq_file methods for the tasks/procs files. The seq_file position is the
* next pid to display; the seq_file iterator is a pointer to the pid
- * in the cgroup->tasks_pids array.
+ * in the cgroup->l->list array.
*/
-static void *cgroup_tasks_start(struct seq_file *s, loff_t *pos)
+static void *cgroup_pidlist_start(struct seq_file *s, loff_t *pos)
{
/*
* Initially we receive a position value that corresponds to
@@ -2254,48 +2619,45 @@ static void *cgroup_tasks_start(struct seq_file *s, loff_t *pos)
* after a seek to the start). Use a binary-search to find the
* next pid to display, if any
*/
- struct cgroup_pids *cp = s->private;
- struct cgroup *cgrp = cp->cgrp;
+ struct cgroup_pidlist *l = s->private;
int index = 0, pid = *pos;
int *iter;
- down_read(&cgrp->pids_mutex);
+ down_read(&l->mutex);
if (pid) {
- int end = cp->length;
+ int end = l->length;
while (index < end) {
int mid = (index + end) / 2;
- if (cp->tasks_pids[mid] == pid) {
+ if (l->list[mid] == pid) {
index = mid;
break;
- } else if (cp->tasks_pids[mid] <= pid)
+ } else if (l->list[mid] <= pid)
index = mid + 1;
else
end = mid;
}
}
/* If we're off the end of the array, we're done */
- if (index >= cp->length)
+ if (index >= l->length)
return NULL;
/* Update the abstract position to be the actual pid that we found */
- iter = cp->tasks_pids + index;
+ iter = l->list + index;
*pos = *iter;
return iter;
}
-static void cgroup_tasks_stop(struct seq_file *s, void *v)
+static void cgroup_pidlist_stop(struct seq_file *s, void *v)
{
- struct cgroup_pids *cp = s->private;
- struct cgroup *cgrp = cp->cgrp;
- up_read(&cgrp->pids_mutex);
+ struct cgroup_pidlist *l = s->private;
+ up_read(&l->mutex);
}
-static void *cgroup_tasks_next(struct seq_file *s, void *v, loff_t *pos)
+static void *cgroup_pidlist_next(struct seq_file *s, void *v, loff_t *pos)
{
- struct cgroup_pids *cp = s->private;
- int *p = v;
- int *end = cp->tasks_pids + cp->length;
-
+ struct cgroup_pidlist *l = s->private;
+ pid_t *p = v;
+ pid_t *end = l->list + l->length;
/*
* Advance to the next pid in the array. If this goes off the
* end, we're done
@@ -2309,124 +2671,107 @@ static void *cgroup_tasks_next(struct seq_file *s, void *v, loff_t *pos)
}
}
-static int cgroup_tasks_show(struct seq_file *s, void *v)
+static int cgroup_pidlist_show(struct seq_file *s, void *v)
{
return seq_printf(s, "%d\n", *(int *)v);
}
-static struct seq_operations cgroup_tasks_seq_operations = {
- .start = cgroup_tasks_start,
- .stop = cgroup_tasks_stop,
- .next = cgroup_tasks_next,
- .show = cgroup_tasks_show,
+/*
+ * seq_operations functions for iterating on pidlists through seq_file -
+ * independent of whether it's tasks or procs
+ */
+static const struct seq_operations cgroup_pidlist_seq_operations = {
+ .start = cgroup_pidlist_start,
+ .stop = cgroup_pidlist_stop,
+ .next = cgroup_pidlist_next,
+ .show = cgroup_pidlist_show,
};
-static void release_cgroup_pid_array(struct cgroup_pids *cp)
+static void cgroup_release_pid_array(struct cgroup_pidlist *l)
{
- struct cgroup *cgrp = cp->cgrp;
-
- down_write(&cgrp->pids_mutex);
- BUG_ON(!cp->use_count);
- if (!--cp->use_count) {
- list_del(&cp->list);
- put_pid_ns(cp->ns);
- kfree(cp->tasks_pids);
- kfree(cp);
+ /*
+ * the case where we're the last user of this particular pidlist will
+ * have us remove it from the cgroup's list, which entails taking the
+ * mutex. since in pidlist_find the pidlist->lock depends on cgroup->
+ * pidlist_mutex, we have to take pidlist_mutex first.
+ */
+ mutex_lock(&l->owner->pidlist_mutex);
+ down_write(&l->mutex);
+ BUG_ON(!l->use_count);
+ if (!--l->use_count) {
+ /* we're the last user if refcount is 0; remove and free */
+ list_del(&l->links);
+ mutex_unlock(&l->owner->pidlist_mutex);
+ pidlist_free(l->list);
+ put_pid_ns(l->key.ns);
+ up_write(&l->mutex);
+ kfree(l);
+ return;
}
- up_write(&cgrp->pids_mutex);
+ mutex_unlock(&l->owner->pidlist_mutex);
+ up_write(&l->mutex);
}
-static int cgroup_tasks_release(struct inode *inode, struct file *file)
+static int cgroup_pidlist_release(struct inode *inode, struct file *file)
{
- struct seq_file *seq;
- struct cgroup_pids *cp;
-
+ struct cgroup_pidlist *l;
if (!(file->f_mode & FMODE_READ))
return 0;
-
- seq = file->private_data;
- cp = seq->private;
-
- release_cgroup_pid_array(cp);
+ /*
+ * the seq_file will only be initialized if the file was opened for
+ * reading; hence we check if it's not null only in that case.
+ */
+ l = ((struct seq_file *)file->private_data)->private;
+ cgroup_release_pid_array(l);
return seq_release(inode, file);
}
-static struct file_operations cgroup_tasks_operations = {
+static const struct file_operations cgroup_pidlist_operations = {
.read = seq_read,
.llseek = seq_lseek,
.write = cgroup_file_write,
- .release = cgroup_tasks_release,
+ .release = cgroup_pidlist_release,
};
/*
- * Handle an open on 'tasks' file. Prepare an array containing the
- * process id's of tasks currently attached to the cgroup being opened.
+ * The following functions handle opens on a file that displays a pidlist
+ * (tasks or procs). Prepare an array of the process/thread IDs of whoever's
+ * in the cgroup.
*/
-
-static int cgroup_tasks_open(struct inode *unused, struct file *file)
+/* helper function for the two below it */
+static int cgroup_pidlist_open(struct file *file, enum cgroup_filetype type)
{
struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent);
- struct pid_namespace *ns = current->nsproxy->pid_ns;
- struct cgroup_pids *cp;
- pid_t *pidarray;
- int npids;
+ struct cgroup_pidlist *l;
int retval;
/* Nothing to do for write-only files */
if (!(file->f_mode & FMODE_READ))
return 0;
- /*
- * If cgroup gets more users after we read count, we won't have
- * enough space - tough. This race is indistinguishable to the
- * caller from the case that the additional cgroup users didn't
- * show up until sometime later on.
- */
- npids = cgroup_task_count(cgrp);
- pidarray = kmalloc(npids * sizeof(pid_t), GFP_KERNEL);
- if (!pidarray)
- return -ENOMEM;
- npids = pid_array_load(pidarray, npids, cgrp);
- sort(pidarray, npids, sizeof(pid_t), cmppid, NULL);
-
- /*
- * Store the array in the cgroup, freeing the old
- * array if necessary
- */
- down_write(&cgrp->pids_mutex);
-
- list_for_each_entry(cp, &cgrp->pids_list, list) {
- if (ns == cp->ns)
- goto found;
- }
-
- cp = kzalloc(sizeof(*cp), GFP_KERNEL);
- if (!cp) {
- up_write(&cgrp->pids_mutex);
- kfree(pidarray);
- return -ENOMEM;
- }
- cp->cgrp = cgrp;
- cp->ns = ns;
- get_pid_ns(ns);
- list_add(&cp->list, &cgrp->pids_list);
-found:
- kfree(cp->tasks_pids);
- cp->tasks_pids = pidarray;
- cp->length = npids;
- cp->use_count++;
- up_write(&cgrp->pids_mutex);
-
- file->f_op = &cgroup_tasks_operations;
+ /* have the array populated */
+ retval = pidlist_array_load(cgrp, type, &l);
+ if (retval)
+ return retval;
+ /* configure file information */
+ file->f_op = &cgroup_pidlist_operations;
- retval = seq_open(file, &cgroup_tasks_seq_operations);
+ retval = seq_open(file, &cgroup_pidlist_seq_operations);
if (retval) {
- release_cgroup_pid_array(cp);
+ cgroup_release_pid_array(l);
return retval;
}
- ((struct seq_file *)file->private_data)->private = cp;
+ ((struct seq_file *)file->private_data)->private = l;
return 0;
}
+static int cgroup_tasks_open(struct inode *unused, struct file *file)
+{
+ return cgroup_pidlist_open(file, CGROUP_FILE_TASKS);
+}
+static int cgroup_procs_open(struct inode *unused, struct file *file)
+{
+ return cgroup_pidlist_open(file, CGROUP_FILE_PROCS);
+}
static u64 cgroup_read_notify_on_release(struct cgroup *cgrp,
struct cftype *cft)
@@ -2449,21 +2794,27 @@ static int cgroup_write_notify_on_release(struct cgroup *cgrp,
/*
* for the common functions, 'private' gives the type of file
*/
+/* for hysterical raisins, we can't put this on the older files */
+#define CGROUP_FILE_GENERIC_PREFIX "cgroup."
static struct cftype files[] = {
{
.name = "tasks",
.open = cgroup_tasks_open,
.write_u64 = cgroup_tasks_write,
- .release = cgroup_tasks_release,
- .private = FILE_TASKLIST,
+ .release = cgroup_pidlist_release,
.mode = S_IRUGO | S_IWUSR,
},
-
+ {
+ .name = CGROUP_FILE_GENERIC_PREFIX "procs",
+ .open = cgroup_procs_open,
+ /* .write_u64 = cgroup_procs_write, TODO */
+ .release = cgroup_pidlist_release,
+ .mode = S_IRUGO,
+ },
{
.name = "notify_on_release",
.read_u64 = cgroup_read_notify_on_release,
.write_u64 = cgroup_write_notify_on_release,
- .private = FILE_NOTIFY_ON_RELEASE,
},
};
@@ -2472,7 +2823,6 @@ static struct cftype cft_release_agent = {
.read_seq_string = cgroup_release_agent_show,
.write_string = cgroup_release_agent_write,
.max_write_len = PATH_MAX,
- .private = FILE_RELEASE_AGENT,
};
static int cgroup_populate_dir(struct cgroup *cgrp)
@@ -2879,6 +3229,7 @@ int __init cgroup_init_early(void)
init_task.cgroups = &init_css_set;
init_css_set_link.cg = &init_css_set;
+ init_css_set_link.cgrp = dummytop;
list_add(&init_css_set_link.cgrp_link_list,
&rootnode.top_cgroup.css_sets);
list_add(&init_css_set_link.cg_link_list,
@@ -2933,7 +3284,7 @@ int __init cgroup_init(void)
/* Add init_css_set to the hash table */
hhead = css_set_hash(init_css_set.subsys);
hlist_add_head(&init_css_set.hlist, hhead);
-
+ BUG_ON(!init_root_id(&rootnode));
err = register_filesystem(&cgroup_fs_type);
if (err < 0)
goto out;
@@ -2986,15 +3337,16 @@ static int proc_cgroup_show(struct seq_file *m, void *v)
for_each_active_root(root) {
struct cgroup_subsys *ss;
struct cgroup *cgrp;
- int subsys_id;
int count = 0;
- seq_printf(m, "%lu:", root->subsys_bits);
+ seq_printf(m, "%d:", root->hierarchy_id);
for_each_subsys(root, ss)
seq_printf(m, "%s%s", count++ ? "," : "", ss->name);
+ if (strlen(root->name))
+ seq_printf(m, "%sname=%s", count ? "," : "",
+ root->name);
seq_putc(m, ':');
- get_first_subsys(&root->top_cgroup, NULL, &subsys_id);
- cgrp = task_cgroup(tsk, subsys_id);
+ cgrp = task_cgroup_from_root(tsk, root);
retval = cgroup_path(cgrp, buf, PAGE_SIZE);
if (retval < 0)
goto out_unlock;
@@ -3017,7 +3369,7 @@ static int cgroup_open(struct inode *inode, struct file *file)
return single_open(file, proc_cgroup_show, pid);
}
-struct file_operations proc_cgroup_operations = {
+const struct file_operations proc_cgroup_operations = {
.open = cgroup_open,
.read = seq_read,
.llseek = seq_lseek,
@@ -3033,8 +3385,8 @@ static int proc_cgroupstats_show(struct seq_file *m, void *v)
mutex_lock(&cgroup_mutex);
for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
struct cgroup_subsys *ss = subsys[i];
- seq_printf(m, "%s\t%lu\t%d\t%d\n",
- ss->name, ss->root->subsys_bits,
+ seq_printf(m, "%s\t%d\t%d\t%d\n",
+ ss->name, ss->root->hierarchy_id,
ss->root->number_of_cgroups, !ss->disabled);
}
mutex_unlock(&cgroup_mutex);
@@ -3046,7 +3398,7 @@ static int cgroupstats_open(struct inode *inode, struct file *file)
return single_open(file, proc_cgroupstats_show, NULL);
}
-static struct file_operations proc_cgroupstats_operations = {
+static const struct file_operations proc_cgroupstats_operations = {
.open = cgroupstats_open,
.read = seq_read,
.llseek = seq_lseek,
@@ -3320,13 +3672,11 @@ int cgroup_is_descendant(const struct cgroup *cgrp, struct task_struct *task)
{
int ret;
struct cgroup *target;
- int subsys_id;
if (cgrp == dummytop)
return 1;
- get_first_subsys(cgrp, NULL, &subsys_id);
- target = task_cgroup(task, subsys_id);
+ target = task_cgroup_from_root(task, cgrp->root);
while (cgrp != target && cgrp!= cgrp->top_cgroup)
cgrp = cgrp->parent;
ret = (cgrp == target);
@@ -3358,8 +3708,10 @@ static void check_for_release(struct cgroup *cgrp)
void __css_put(struct cgroup_subsys_state *css)
{
struct cgroup *cgrp = css->cgroup;
+ int val;
rcu_read_lock();
- if (atomic_dec_return(&css->refcnt) == 1) {
+ val = atomic_dec_return(&css->refcnt);
+ if (val == 1) {
if (notify_on_release(cgrp)) {
set_bit(CGRP_RELEASABLE, &cgrp->flags);
check_for_release(cgrp);
@@ -3367,6 +3719,7 @@ void __css_put(struct cgroup_subsys_state *css)
cgroup_wakeup_rmdir_waiter(cgrp);
}
rcu_read_unlock();
+ WARN_ON_ONCE(val < 1);
}
/*
@@ -3693,3 +4046,154 @@ css_get_next(struct cgroup_subsys *ss, int id,
return ret;
}
+#ifdef CONFIG_CGROUP_DEBUG
+static struct cgroup_subsys_state *debug_create(struct cgroup_subsys *ss,
+ struct cgroup *cont)
+{
+ struct cgroup_subsys_state *css = kzalloc(sizeof(*css), GFP_KERNEL);
+
+ if (!css)
+ return ERR_PTR(-ENOMEM);
+
+ return css;
+}
+
+static void debug_destroy(struct cgroup_subsys *ss, struct cgroup *cont)
+{
+ kfree(cont->subsys[debug_subsys_id]);
+}
+
+static u64 cgroup_refcount_read(struct cgroup *cont, struct cftype *cft)
+{
+ return atomic_read(&cont->count);
+}
+
+static u64 debug_taskcount_read(struct cgroup *cont, struct cftype *cft)
+{
+ return cgroup_task_count(cont);
+}
+
+static u64 current_css_set_read(struct cgroup *cont, struct cftype *cft)
+{
+ return (u64)(unsigned long)current->cgroups;
+}
+
+static u64 current_css_set_refcount_read(struct cgroup *cont,
+ struct cftype *cft)
+{
+ u64 count;
+
+ rcu_read_lock();
+ count = atomic_read(&current->cgroups->refcount);
+ rcu_read_unlock();
+ return count;
+}
+
+static int current_css_set_cg_links_read(struct cgroup *cont,
+ struct cftype *cft,
+ struct seq_file *seq)
+{
+ struct cg_cgroup_link *link;
+ struct css_set *cg;
+
+ read_lock(&css_set_lock);
+ rcu_read_lock();
+ cg = rcu_dereference(current->cgroups);
+ list_for_each_entry(link, &cg->cg_links, cg_link_list) {
+ struct cgroup *c = link->cgrp;
+ const char *name;
+
+ if (c->dentry)
+ name = c->dentry->d_name.name;
+ else
+ name = "?";
+ seq_printf(seq, "Root %d group %s\n",
+ c->root->hierarchy_id, name);
+ }
+ rcu_read_unlock();
+ read_unlock(&css_set_lock);
+ return 0;
+}
+
+#define MAX_TASKS_SHOWN_PER_CSS 25
+static int cgroup_css_links_read(struct cgroup *cont,
+ struct cftype *cft,
+ struct seq_file *seq)
+{
+ struct cg_cgroup_link *link;
+
+ read_lock(&css_set_lock);
+ list_for_each_entry(link, &cont->css_sets, cgrp_link_list) {
+ struct css_set *cg = link->cg;
+ struct task_struct *task;
+ int count = 0;
+ seq_printf(seq, "css_set %p\n", cg);
+ list_for_each_entry(task, &cg->tasks, cg_list) {
+ if (count++ > MAX_TASKS_SHOWN_PER_CSS) {
+ seq_puts(seq, " ...\n");
+ break;
+ } else {
+ seq_printf(seq, " task %d\n",
+ task_pid_vnr(task));
+ }
+ }
+ }
+ read_unlock(&css_set_lock);
+ return 0;
+}
+
+static u64 releasable_read(struct cgroup *cgrp, struct cftype *cft)
+{
+ return test_bit(CGRP_RELEASABLE, &cgrp->flags);
+}
+
+static struct cftype debug_files[] = {
+ {
+ .name = "cgroup_refcount",
+ .read_u64 = cgroup_refcount_read,
+ },
+ {
+ .name = "taskcount",
+ .read_u64 = debug_taskcount_read,
+ },
+
+ {
+ .name = "current_css_set",
+ .read_u64 = current_css_set_read,
+ },
+
+ {
+ .name = "current_css_set_refcount",
+ .read_u64 = current_css_set_refcount_read,
+ },
+
+ {
+ .name = "current_css_set_cg_links",
+ .read_seq_string = current_css_set_cg_links_read,
+ },
+
+ {
+ .name = "cgroup_css_links",
+ .read_seq_string = cgroup_css_links_read,
+ },
+
+ {
+ .name = "releasable",
+ .read_u64 = releasable_read,
+ },
+};
+
+static int debug_populate(struct cgroup_subsys *ss, struct cgroup *cont)
+{
+ return cgroup_add_files(cont, ss, debug_files,
+ ARRAY_SIZE(debug_files));
+}
+
+struct cgroup_subsys debug_subsys = {
+ .name = "debug",
+ .create = debug_create,
+ .destroy = debug_destroy,
+ .populate = debug_populate,
+ .subsys_id = debug_subsys_id,
+};
+#endif /* CONFIG_CGROUP_DEBUG */
diff --git a/kernel/cgroup_debug.c b/kernel/cgroup_debug.c
deleted file mode 100644
index 0c92d797baa..00000000000
--- a/kernel/cgroup_debug.c
+++ /dev/null
@@ -1,105 +0,0 @@
-/*
- * kernel/cgroup_debug.c - Example cgroup subsystem that
- * exposes debug info
- *
- * Copyright (C) Google Inc, 2007
- *
- * Developed by Paul Menage (menage@google.com)
- *
- */
-
-#include <linux/cgroup.h>
-#include <linux/fs.h>
-#include <linux/slab.h>
-#include <linux/rcupdate.h>
-
-#include <asm/atomic.h>
-
-static struct cgroup_subsys_state *debug_create(struct cgroup_subsys *ss,
- struct cgroup *cont)
-{
- struct cgroup_subsys_state *css = kzalloc(sizeof(*css), GFP_KERNEL);
-
- if (!css)
- return ERR_PTR(-ENOMEM);
-
- return css;
-}
-
-static void debug_destroy(struct cgroup_subsys *ss, struct cgroup *cont)
-{
- kfree(cont->subsys[debug_subsys_id]);
-}
-
-static u64 cgroup_refcount_read(struct cgroup *cont, struct cftype *cft)
-{
- return atomic_read(&cont->count);
-}
-
-static u64 taskcount_read(struct cgroup *cont, struct cftype *cft)
-{
- u64 count;
-
- count = cgroup_task_count(cont);
- return count;
-}
-
-static u64 current_css_set_read(struct cgroup *cont, struct cftype *cft)
-{
- return (u64)(long)current->cgroups;
-}
-
-static u64 current_css_set_refcount_read(struct cgroup *cont,
- struct cftype *cft)
-{
- u64 count;
-
- rcu_read_lock();
- count = atomic_read(&current->cgroups->refcount);
- rcu_read_unlock();
- return count;
-}
-
-static u64 releasable_read(struct cgroup *cgrp, struct cftype *cft)
-{
- return test_bit(CGRP_RELEASABLE, &cgrp->flags);
-}
-
-static struct cftype files[] = {
- {
- .name = "cgroup_refcount",
- .read_u64 = cgroup_refcount_read,
- },
- {
- .name = "taskcount",
- .read_u64 = taskcount_read,
- },
-
- {
- .name = "current_css_set",
- .read_u64 = current_css_set_read,
- },
-
- {
- .name = "current_css_set_refcount",
- .read_u64 = current_css_set_refcount_read,
- },
-
- {
- .name = "releasable",
- .read_u64 = releasable_read,
- },
-};
-
-static int debug_populate(struct cgroup_subsys *ss, struct cgroup *cont)
-{
- return cgroup_add_files(cont, ss, files, ARRAY_SIZE(files));
-}
-
-struct cgroup_subsys debug_subsys = {
- .name = "debug",
- .create = debug_create,
- .destroy = debug_destroy,
- .populate = debug_populate,
- .subsys_id = debug_subsys_id,
-};
diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c
index fb249e2bcad..59e9ef6aab4 100644
--- a/kernel/cgroup_freezer.c
+++ b/kernel/cgroup_freezer.c
@@ -159,7 +159,7 @@ static bool is_task_frozen_enough(struct task_struct *task)
*/
static int freezer_can_attach(struct cgroup_subsys *ss,
struct cgroup *new_cgroup,
- struct task_struct *task)
+ struct task_struct *task, bool threadgroup)
{
struct freezer *freezer;
@@ -177,6 +177,19 @@ static int freezer_can_attach(struct cgroup_subsys *ss,
if (freezer->state == CGROUP_FROZEN)
return -EBUSY;
+ if (threadgroup) {
+ struct task_struct *c;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(c, &task->thread_group, thread_group) {
+ if (is_task_frozen_enough(c)) {
+ rcu_read_unlock();
+ return -EBUSY;
+ }
+ }
+ rcu_read_unlock();
+ }
+
return 0;
}
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 7e75a41bd50..b5cb469d254 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1324,9 +1324,10 @@ static int fmeter_getrate(struct fmeter *fmp)
static cpumask_var_t cpus_attach;
/* Called by cgroups to determine if a cpuset is usable; cgroup_mutex held */
-static int cpuset_can_attach(struct cgroup_subsys *ss,
- struct cgroup *cont, struct task_struct *tsk)
+static int cpuset_can_attach(struct cgroup_subsys *ss, struct cgroup *cont,
+ struct task_struct *tsk, bool threadgroup)
{
+ int ret;
struct cpuset *cs = cgroup_cs(cont);
if (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed))
@@ -1343,18 +1344,51 @@ static int cpuset_can_attach(struct cgroup_subsys *ss,
if (tsk->flags & PF_THREAD_BOUND)
return -EINVAL;
- return security_task_setscheduler(tsk, 0, NULL);
+ ret = security_task_setscheduler(tsk, 0, NULL);
+ if (ret)
+ return ret;
+ if (threadgroup) {
+ struct task_struct *c;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(c, &tsk->thread_group, thread_group) {
+ ret = security_task_setscheduler(c, 0, NULL);
+ if (ret) {
+ rcu_read_unlock();
+ return ret;
+ }
+ }
+ rcu_read_unlock();
+ }
+ return 0;
+}
+
+static void cpuset_attach_task(struct task_struct *tsk, nodemask_t *to,
+ struct cpuset *cs)
+{
+ int err;
+ /*
+ * can_attach beforehand should guarantee that this doesn't fail.
+ * TODO: have a better way to handle failure here
+ */
+ err = set_cpus_allowed_ptr(tsk, cpus_attach);
+ WARN_ON_ONCE(err);
+
+ task_lock(tsk);
+ cpuset_change_task_nodemask(tsk, to);
+ task_unlock(tsk);
+ cpuset_update_task_spread_flag(cs, tsk);
+
}
-static void cpuset_attach(struct cgroup_subsys *ss,
- struct cgroup *cont, struct cgroup *oldcont,
- struct task_struct *tsk)
+static void cpuset_attach(struct cgroup_subsys *ss, struct cgroup *cont,
+ struct cgroup *oldcont, struct task_struct *tsk,
+ bool threadgroup)
{
nodemask_t from, to;
struct mm_struct *mm;
struct cpuset *cs = cgroup_cs(cont);
struct cpuset *oldcs = cgroup_cs(oldcont);
- int err;
if (cs == &top_cpuset) {
cpumask_copy(cpus_attach, cpu_possible_mask);
@@ -1363,15 +1397,19 @@ static void cpuset_attach(struct cgroup_subsys *ss,
guarantee_online_cpus(cs, cpus_attach);
guarantee_online_mems(cs, &to);
}
- err = set_cpus_allowed_ptr(tsk, cpus_attach);
- if (err)
- return;
- task_lock(tsk);
- cpuset_change_task_nodemask(tsk, &to);
- task_unlock(tsk);
- cpuset_update_task_spread_flag(cs, tsk);
+ /* do per-task migration stuff possibly for each in the threadgroup */
+ cpuset_attach_task(tsk, &to, cs);
+ if (threadgroup) {
+ struct task_struct *c;
+ rcu_read_lock();
+ list_for_each_entry_rcu(c, &tsk->thread_group, thread_group) {
+ cpuset_attach_task(c, &to, cs);
+ }
+ rcu_read_unlock();
+ }
+ /* change mm; only needs to be done once even if threadgroup */
from = oldcs->mems_allowed;
to = cs->mems_allowed;
mm = get_task_mm(tsk);
diff --git a/kernel/cred.c b/kernel/cred.c
index d7f7a01082e..dd76cfe5f5b 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -782,6 +782,25 @@ EXPORT_SYMBOL(set_create_files_as);
#ifdef CONFIG_DEBUG_CREDENTIALS
+bool creds_are_invalid(const struct cred *cred)
+{
+ if (cred->magic != CRED_MAGIC)
+ return true;
+ if (atomic_read(&cred->usage) < atomic_read(&cred->subscribers))
+ return true;
+#ifdef CONFIG_SECURITY_SELINUX
+ if (selinux_is_enabled()) {
+ if ((unsigned long) cred->security < PAGE_SIZE)
+ return true;
+ if ((*(u32 *)cred->security & 0xffffff00) ==
+ (POISON_FREE << 24 | POISON_FREE << 16 | POISON_FREE << 8))
+ return true;
+ }
+#endif
+ return false;
+}
+EXPORT_SYMBOL(creds_are_invalid);
+
/*
* dump invalid credentials
*/
diff --git a/kernel/exit.c b/kernel/exit.c
index ae5d8660ddf..5859f598c95 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -47,7 +47,7 @@
#include <linux/tracehook.h>
#include <linux/fs_struct.h>
#include <linux/init_task.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
#include <trace/events/sched.h>
#include <asm/uaccess.h>
@@ -154,8 +154,8 @@ static void delayed_put_task_struct(struct rcu_head *rhp)
{
struct task_struct *tsk = container_of(rhp, struct task_struct, rcu);
-#ifdef CONFIG_PERF_COUNTERS
- WARN_ON_ONCE(tsk->perf_counter_ctxp);
+#ifdef CONFIG_PERF_EVENTS
+ WARN_ON_ONCE(tsk->perf_event_ctxp);
#endif
trace_sched_process_free(tsk);
put_task_struct(tsk);
@@ -359,8 +359,10 @@ void __set_special_pids(struct pid *pid)
{
struct task_struct *curr = current->group_leader;
- if (task_session(curr) != pid)
+ if (task_session(curr) != pid) {
change_pid(curr, PIDTYPE_SID, pid);
+ proc_sid_connector(curr);
+ }
if (task_pgrp(curr) != pid)
change_pid(curr, PIDTYPE_PGID, pid);
@@ -945,6 +947,8 @@ NORET_TYPE void do_exit(long code)
if (group_dead) {
hrtimer_cancel(&tsk->signal->real_timer);
exit_itimers(tsk->signal);
+ if (tsk->mm)
+ setmax_mm_hiwater_rss(&tsk->signal->maxrss, tsk->mm);
}
acct_collect(code, group_dead);
if (group_dead)
@@ -972,8 +976,6 @@ NORET_TYPE void do_exit(long code)
disassociate_ctty(1);
module_put(task_thread_info(tsk)->exec_domain->module);
- if (tsk->binfmt)
- module_put(tsk->binfmt->module);
proc_exit_connector(tsk);
@@ -981,7 +983,7 @@ NORET_TYPE void do_exit(long code)
* Flush inherited counters to the parent - before the parent
* gets woken up by child-exit notifications.
*/
- perf_counter_exit_task(tsk);
+ perf_event_exit_task(tsk);
exit_notify(tsk, group_dead);
#ifdef CONFIG_NUMA
@@ -1093,28 +1095,28 @@ struct wait_opts {
int __user *wo_stat;
struct rusage __user *wo_rusage;
+ wait_queue_t child_wait;
int notask_error;
};
-static struct pid *task_pid_type(struct task_struct *task, enum pid_type type)
+static inline
+struct pid *task_pid_type(struct task_struct *task, enum pid_type type)
{
- struct pid *pid = NULL;
- if (type == PIDTYPE_PID)
- pid = task->pids[type].pid;
- else if (type < PIDTYPE_MAX)
- pid = task->group_leader->pids[type].pid;
- return pid;
+ if (type != PIDTYPE_PID)
+ task = task->group_leader;
+ return task->pids[type].pid;
}
-static int eligible_child(struct wait_opts *wo, struct task_struct *p)
+static int eligible_pid(struct wait_opts *wo, struct task_struct *p)
{
- int err;
-
- if (wo->wo_type < PIDTYPE_MAX) {
- if (task_pid_type(p, wo->wo_type) != wo->wo_pid)
- return 0;
- }
+ return wo->wo_type == PIDTYPE_MAX ||
+ task_pid_type(p, wo->wo_type) == wo->wo_pid;
+}
+static int eligible_child(struct wait_opts *wo, struct task_struct *p)
+{
+ if (!eligible_pid(wo, p))
+ return 0;
/* Wait for all children (clone and not) if __WALL is set;
* otherwise, wait for clone children *only* if __WCLONE is
* set; otherwise, wait for non-clone children *only*. (Note:
@@ -1124,10 +1126,6 @@ static int eligible_child(struct wait_opts *wo, struct task_struct *p)
&& !(wo->wo_flags & __WALL))
return 0;
- err = security_task_wait(p);
- if (err)
- return err;
-
return 1;
}
@@ -1140,18 +1138,20 @@ static int wait_noreap_copyout(struct wait_opts *wo, struct task_struct *p,
put_task_struct(p);
infop = wo->wo_info;
- if (!retval)
- retval = put_user(SIGCHLD, &infop->si_signo);
- if (!retval)
- retval = put_user(0, &infop->si_errno);
- if (!retval)
- retval = put_user((short)why, &infop->si_code);
- if (!retval)
- retval = put_user(pid, &infop->si_pid);
- if (!retval)
- retval = put_user(uid, &infop->si_uid);
- if (!retval)
- retval = put_user(status, &infop->si_status);
+ if (infop) {
+ if (!retval)
+ retval = put_user(SIGCHLD, &infop->si_signo);
+ if (!retval)
+ retval = put_user(0, &infop->si_errno);
+ if (!retval)
+ retval = put_user((short)why, &infop->si_code);
+ if (!retval)
+ retval = put_user(pid, &infop->si_pid);
+ if (!retval)
+ retval = put_user(uid, &infop->si_uid);
+ if (!retval)
+ retval = put_user(status, &infop->si_status);
+ }
if (!retval)
retval = pid;
return retval;
@@ -1208,6 +1208,7 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
if (likely(!traced) && likely(!task_detached(p))) {
struct signal_struct *psig;
struct signal_struct *sig;
+ unsigned long maxrss;
/*
* The resource counters for the group leader are in its
@@ -1256,6 +1257,9 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
psig->coublock +=
task_io_get_oublock(p) +
sig->oublock + sig->coublock;
+ maxrss = max(sig->maxrss, sig->cmaxrss);
+ if (psig->cmaxrss < maxrss)
+ psig->cmaxrss = maxrss;
task_io_accounting_add(&psig->ioac, &p->ioac);
task_io_accounting_add(&psig->ioac, &sig->ioac);
spin_unlock_irq(&p->real_parent->sighand->siglock);
@@ -1477,13 +1481,14 @@ static int wait_task_continued(struct wait_opts *wo, struct task_struct *p)
* then ->notask_error is 0 if @p is an eligible child,
* or another error from security_task_wait(), or still -ECHILD.
*/
-static int wait_consider_task(struct wait_opts *wo, struct task_struct *parent,
- int ptrace, struct task_struct *p)
+static int wait_consider_task(struct wait_opts *wo, int ptrace,
+ struct task_struct *p)
{
int ret = eligible_child(wo, p);
if (!ret)
return ret;
+ ret = security_task_wait(p);
if (unlikely(ret < 0)) {
/*
* If we have not yet seen any eligible child,
@@ -1545,7 +1550,7 @@ static int do_wait_thread(struct wait_opts *wo, struct task_struct *tsk)
* Do not consider detached threads.
*/
if (!task_detached(p)) {
- int ret = wait_consider_task(wo, tsk, 0, p);
+ int ret = wait_consider_task(wo, 0, p);
if (ret)
return ret;
}
@@ -1559,7 +1564,7 @@ static int ptrace_do_wait(struct wait_opts *wo, struct task_struct *tsk)
struct task_struct *p;
list_for_each_entry(p, &tsk->ptraced, ptrace_entry) {
- int ret = wait_consider_task(wo, tsk, 1, p);
+ int ret = wait_consider_task(wo, 1, p);
if (ret)
return ret;
}
@@ -1567,15 +1572,38 @@ static int ptrace_do_wait(struct wait_opts *wo, struct task_struct *tsk)
return 0;
}
+static int child_wait_callback(wait_queue_t *wait, unsigned mode,
+ int sync, void *key)
+{
+ struct wait_opts *wo = container_of(wait, struct wait_opts,
+ child_wait);
+ struct task_struct *p = key;
+
+ if (!eligible_pid(wo, p))
+ return 0;
+
+ if ((wo->wo_flags & __WNOTHREAD) && wait->private != p->parent)
+ return 0;
+
+ return default_wake_function(wait, mode, sync, key);
+}
+
+void __wake_up_parent(struct task_struct *p, struct task_struct *parent)
+{
+ __wake_up_sync_key(&parent->signal->wait_chldexit,
+ TASK_INTERRUPTIBLE, 1, p);
+}
+
static long do_wait(struct wait_opts *wo)
{
- DECLARE_WAITQUEUE(wait, current);
struct task_struct *tsk;
int retval;
trace_sched_process_wait(wo->wo_pid);
- add_wait_queue(&current->signal->wait_chldexit,&wait);
+ init_waitqueue_func_entry(&wo->child_wait, child_wait_callback);
+ wo->child_wait.private = current;
+ add_wait_queue(&current->signal->wait_chldexit, &wo->child_wait);
repeat:
/*
* If there is nothing that can match our critiera just get out.
@@ -1616,32 +1644,7 @@ notask:
}
end:
__set_current_state(TASK_RUNNING);
- remove_wait_queue(&current->signal->wait_chldexit,&wait);
- if (wo->wo_info) {
- struct siginfo __user *infop = wo->wo_info;
-
- if (retval > 0)
- retval = 0;
- else {
- /*
- * For a WNOHANG return, clear out all the fields
- * we would set so the user can easily tell the
- * difference.
- */
- if (!retval)
- retval = put_user(0, &infop->si_signo);
- if (!retval)
- retval = put_user(0, &infop->si_errno);
- if (!retval)
- retval = put_user(0, &infop->si_code);
- if (!retval)
- retval = put_user(0, &infop->si_pid);
- if (!retval)
- retval = put_user(0, &infop->si_uid);
- if (!retval)
- retval = put_user(0, &infop->si_status);
- }
- }
+ remove_wait_queue(&current->signal->wait_chldexit, &wo->child_wait);
return retval;
}
@@ -1686,6 +1689,29 @@ SYSCALL_DEFINE5(waitid, int, which, pid_t, upid, struct siginfo __user *,
wo.wo_stat = NULL;
wo.wo_rusage = ru;
ret = do_wait(&wo);
+
+ if (ret > 0) {
+ ret = 0;
+ } else if (infop) {
+ /*
+ * For a WNOHANG return, clear out all the fields
+ * we would set so the user can easily tell the
+ * difference.
+ */
+ if (!ret)
+ ret = put_user(0, &infop->si_signo);
+ if (!ret)
+ ret = put_user(0, &infop->si_errno);
+ if (!ret)
+ ret = put_user(0, &infop->si_code);
+ if (!ret)
+ ret = put_user(0, &infop->si_pid);
+ if (!ret)
+ ret = put_user(0, &infop->si_uid);
+ if (!ret)
+ ret = put_user(0, &infop->si_status);
+ }
+
put_pid(pid);
/* avoid REGPARM breakage on x86: */
diff --git a/kernel/fork.c b/kernel/fork.c
index bfee931ee3f..266c6af6ef1 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -49,6 +49,7 @@
#include <linux/ftrace.h>
#include <linux/profile.h>
#include <linux/rmap.h>
+#include <linux/ksm.h>
#include <linux/acct.h>
#include <linux/tsacct_kern.h>
#include <linux/cn_proc.h>
@@ -61,7 +62,8 @@
#include <linux/blkdev.h>
#include <linux/fs_struct.h>
#include <linux/magic.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
+#include <linux/posix-timers.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
@@ -136,9 +138,17 @@ struct kmem_cache *vm_area_cachep;
/* SLAB cache for mm_struct structures (tsk->mm) */
static struct kmem_cache *mm_cachep;
+static void account_kernel_stack(struct thread_info *ti, int account)
+{
+ struct zone *zone = page_zone(virt_to_page(ti));
+
+ mod_zone_page_state(zone, NR_KERNEL_STACK, account);
+}
+
void free_task(struct task_struct *tsk)
{
prop_local_destroy_single(&tsk->dirties);
+ account_kernel_stack(tsk->stack, -1);
free_thread_info(tsk->stack);
rt_mutex_debug_task_free(tsk);
ftrace_graph_exit_task(tsk);
@@ -253,6 +263,9 @@ static struct task_struct *dup_task_struct(struct task_struct *orig)
tsk->btrace_seq = 0;
#endif
tsk->splice_pipe = NULL;
+
+ account_kernel_stack(ti, 1);
+
return tsk;
out:
@@ -288,6 +301,9 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
rb_link = &mm->mm_rb.rb_node;
rb_parent = NULL;
pprev = &mm->mmap;
+ retval = ksm_fork(mm, oldmm);
+ if (retval)
+ goto out;
for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) {
struct file *file;
@@ -418,22 +434,30 @@ __setup("coredump_filter=", coredump_filter_setup);
#include <linux/init_task.h>
+static void mm_init_aio(struct mm_struct *mm)
+{
+#ifdef CONFIG_AIO
+ spin_lock_init(&mm->ioctx_lock);
+ INIT_HLIST_HEAD(&mm->ioctx_list);
+#endif
+}
+
static struct mm_struct * mm_init(struct mm_struct * mm, struct task_struct *p)
{
atomic_set(&mm->mm_users, 1);
atomic_set(&mm->mm_count, 1);
init_rwsem(&mm->mmap_sem);
INIT_LIST_HEAD(&mm->mmlist);
- mm->flags = (current->mm) ? current->mm->flags : default_dump_filter;
+ mm->flags = (current->mm) ?
+ (current->mm->flags & MMF_INIT_MASK) : default_dump_filter;
mm->core_state = NULL;
mm->nr_ptes = 0;
set_mm_counter(mm, file_rss, 0);
set_mm_counter(mm, anon_rss, 0);
spin_lock_init(&mm->page_table_lock);
- spin_lock_init(&mm->ioctx_lock);
- INIT_HLIST_HEAD(&mm->ioctx_list);
mm->free_area_cache = TASK_UNMAPPED_BASE;
mm->cached_hole_size = ~0UL;
+ mm_init_aio(mm);
mm_init_owner(mm, p);
if (likely(!mm_alloc_pgd(mm))) {
@@ -485,6 +509,7 @@ void mmput(struct mm_struct *mm)
if (atomic_dec_and_test(&mm->mm_users)) {
exit_aio(mm);
+ ksm_exit(mm);
exit_mmap(mm);
set_mm_exe_file(mm, NULL);
if (!list_empty(&mm->mmlist)) {
@@ -493,6 +518,8 @@ void mmput(struct mm_struct *mm)
spin_unlock(&mmlist_lock);
}
put_swap_token(mm);
+ if (mm->binfmt)
+ module_put(mm->binfmt->module);
mmdrop(mm);
}
}
@@ -618,9 +645,14 @@ struct mm_struct *dup_mm(struct task_struct *tsk)
mm->hiwater_rss = get_mm_rss(mm);
mm->hiwater_vm = mm->total_vm;
+ if (mm->binfmt && !try_module_get(mm->binfmt->module))
+ goto free_pt;
+
return mm;
free_pt:
+ /* don't put binfmt in mmput, we haven't got module yet */
+ mm->binfmt = NULL;
mmput(mm);
fail_nomem:
@@ -788,10 +820,10 @@ static void posix_cpu_timers_init_group(struct signal_struct *sig)
thread_group_cputime_init(sig);
/* Expiration times and increments. */
- sig->it_virt_expires = cputime_zero;
- sig->it_virt_incr = cputime_zero;
- sig->it_prof_expires = cputime_zero;
- sig->it_prof_incr = cputime_zero;
+ sig->it[CPUCLOCK_PROF].expires = cputime_zero;
+ sig->it[CPUCLOCK_PROF].incr = cputime_zero;
+ sig->it[CPUCLOCK_VIRT].expires = cputime_zero;
+ sig->it[CPUCLOCK_VIRT].incr = cputime_zero;
/* Cached expiration times. */
sig->cputime_expires.prof_exp = cputime_zero;
@@ -849,6 +881,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
sig->nvcsw = sig->nivcsw = sig->cnvcsw = sig->cnivcsw = 0;
sig->min_flt = sig->maj_flt = sig->cmin_flt = sig->cmaj_flt = 0;
sig->inblock = sig->oublock = sig->cinblock = sig->coublock = 0;
+ sig->maxrss = sig->cmaxrss = 0;
task_io_accounting_init(&sig->ioac);
sig->sum_sched_runtime = 0;
taskstats_tgid_init(sig);
@@ -863,6 +896,8 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
tty_audit_fork(sig);
+ sig->oom_adj = current->signal->oom_adj;
+
return 0;
}
@@ -958,6 +993,16 @@ static struct task_struct *copy_process(unsigned long clone_flags,
if ((clone_flags & CLONE_SIGHAND) && !(clone_flags & CLONE_VM))
return ERR_PTR(-EINVAL);
+ /*
+ * Siblings of global init remain as zombies on exit since they are
+ * not reaped by their parent (swapper). To solve this and to avoid
+ * multi-rooted process trees, prevent global and container-inits
+ * from creating siblings.
+ */
+ if ((clone_flags & CLONE_PARENT) &&
+ current->signal->flags & SIGNAL_UNKILLABLE)
+ return ERR_PTR(-EINVAL);
+
retval = security_task_create(clone_flags);
if (retval)
goto fork_out;
@@ -999,9 +1044,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
if (!try_module_get(task_thread_info(p)->exec_domain->module))
goto bad_fork_cleanup_count;
- if (p->binfmt && !try_module_get(p->binfmt->module))
- goto bad_fork_cleanup_put_domain;
-
p->did_exec = 0;
delayacct_tsk_init(p); /* Must remain after dup_task_struct() */
copy_flags(clone_flags, p);
@@ -1075,10 +1117,12 @@ static struct task_struct *copy_process(unsigned long clone_flags,
p->bts = NULL;
+ p->stack_start = stack_start;
+
/* Perform scheduler related setup. Assign this task to a CPU. */
sched_fork(p, clone_flags);
- retval = perf_counter_init_task(p);
+ retval = perf_event_init_task(p);
if (retval)
goto bad_fork_cleanup_policy;
@@ -1253,7 +1297,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
write_unlock_irq(&tasklist_lock);
proc_fork_connector(p);
cgroup_post_fork(p);
- perf_counter_fork(p);
+ perf_event_fork(p);
return p;
bad_fork_free_pid:
@@ -1280,16 +1324,13 @@ bad_fork_cleanup_semundo:
bad_fork_cleanup_audit:
audit_free(p);
bad_fork_cleanup_policy:
- perf_counter_free_task(p);
+ perf_event_free_task(p);
#ifdef CONFIG_NUMA
mpol_put(p->mempolicy);
bad_fork_cleanup_cgroup:
#endif
cgroup_exit(p, cgroup_callbacks_done);
delayacct_tsk_free(p);
- if (p->binfmt)
- module_put(p->binfmt->module);
-bad_fork_cleanup_put_domain:
module_put(task_thread_info(p)->exec_domain->module);
bad_fork_cleanup_count:
atomic_dec(&p->cred->user->processes);
diff --git a/kernel/futex.c b/kernel/futex.c
index 248dd119a86..b911adceb2c 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -89,36 +89,36 @@ struct futex_pi_state {
union futex_key key;
};
-/*
- * We use this hashed waitqueue instead of a normal wait_queue_t, so
+/**
+ * struct futex_q - The hashed futex queue entry, one per waiting task
+ * @task: the task waiting on the futex
+ * @lock_ptr: the hash bucket lock
+ * @key: the key the futex is hashed on
+ * @pi_state: optional priority inheritance state
+ * @rt_waiter: rt_waiter storage for use with requeue_pi
+ * @requeue_pi_key: the requeue_pi target futex key
+ * @bitset: bitset for the optional bitmasked wakeup
+ *
+ * We use this hashed waitqueue, instead of a normal wait_queue_t, so
* we can wake only the relevant ones (hashed queues may be shared).
*
* A futex_q has a woken state, just like tasks have TASK_RUNNING.
* It is considered woken when plist_node_empty(&q->list) || q->lock_ptr == 0.
* The order of wakup is always to make the first condition true, then
- * wake up q->waiter, then make the second condition true.
+ * the second.
+ *
+ * PI futexes are typically woken before they are removed from the hash list via
+ * the rt_mutex code. See unqueue_me_pi().
*/
struct futex_q {
struct plist_node list;
- /* Waiter reference */
- struct task_struct *task;
- /* Which hash list lock to use: */
+ struct task_struct *task;
spinlock_t *lock_ptr;
-
- /* Key which the futex is hashed on: */
union futex_key key;
-
- /* Optional priority inheritance state: */
struct futex_pi_state *pi_state;
-
- /* rt_waiter storage for requeue_pi: */
struct rt_mutex_waiter *rt_waiter;
-
- /* The expected requeue pi target futex key: */
union futex_key *requeue_pi_key;
-
- /* Bitset for the optional bitmasked wakeup */
u32 bitset;
};
@@ -198,11 +198,12 @@ static void drop_futex_key_refs(union futex_key *key)
}
/**
- * get_futex_key - Get parameters which are the keys for a futex.
- * @uaddr: virtual address of the futex
- * @fshared: 0 for a PROCESS_PRIVATE futex, 1 for PROCESS_SHARED
- * @key: address where result is stored.
- * @rw: mapping needs to be read/write (values: VERIFY_READ, VERIFY_WRITE)
+ * get_futex_key() - Get parameters which are the keys for a futex
+ * @uaddr: virtual address of the futex
+ * @fshared: 0 for a PROCESS_PRIVATE futex, 1 for PROCESS_SHARED
+ * @key: address where result is stored.
+ * @rw: mapping needs to be read/write (values: VERIFY_READ,
+ * VERIFY_WRITE)
*
* Returns a negative error code or 0
* The key words are stored in *key on success.
@@ -288,8 +289,8 @@ void put_futex_key(int fshared, union futex_key *key)
drop_futex_key_refs(key);
}
-/*
- * fault_in_user_writeable - fault in user address and verify RW access
+/**
+ * fault_in_user_writeable() - Fault in user address and verify RW access
* @uaddr: pointer to faulting user space address
*
* Slow path to fixup the fault we just took in the atomic write
@@ -309,8 +310,8 @@ static int fault_in_user_writeable(u32 __user *uaddr)
/**
* futex_top_waiter() - Return the highest priority waiter on a futex
- * @hb: the hash bucket the futex_q's reside in
- * @key: the futex key (to distinguish it from other futex futex_q's)
+ * @hb: the hash bucket the futex_q's reside in
+ * @key: the futex key (to distinguish it from other futex futex_q's)
*
* Must be called with the hb lock held.
*/
@@ -588,7 +589,7 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
}
/**
- * futex_lock_pi_atomic() - atomic work required to acquire a pi aware futex
+ * futex_lock_pi_atomic() - Atomic work required to acquire a pi aware futex
* @uaddr: the pi futex user address
* @hb: the pi futex hash bucket
* @key: the futex key associated with uaddr and hb
@@ -1011,9 +1012,9 @@ void requeue_futex(struct futex_q *q, struct futex_hash_bucket *hb1,
/**
* requeue_pi_wake_futex() - Wake a task that acquired the lock during requeue
- * q: the futex_q
- * key: the key of the requeue target futex
- * hb: the hash_bucket of the requeue target futex
+ * @q: the futex_q
+ * @key: the key of the requeue target futex
+ * @hb: the hash_bucket of the requeue target futex
*
* During futex_requeue, with requeue_pi=1, it is possible to acquire the
* target futex if it is uncontended or via a lock steal. Set the futex_q key
@@ -1350,6 +1351,25 @@ static inline struct futex_hash_bucket *queue_lock(struct futex_q *q)
return hb;
}
+static inline void
+queue_unlock(struct futex_q *q, struct futex_hash_bucket *hb)
+{
+ spin_unlock(&hb->lock);
+ drop_futex_key_refs(&q->key);
+}
+
+/**
+ * queue_me() - Enqueue the futex_q on the futex_hash_bucket
+ * @q: The futex_q to enqueue
+ * @hb: The destination hash bucket
+ *
+ * The hb->lock must be held by the caller, and is released here. A call to
+ * queue_me() is typically paired with exactly one call to unqueue_me(). The
+ * exceptions involve the PI related operations, which may use unqueue_me_pi()
+ * or nothing if the unqueue is done as part of the wake process and the unqueue
+ * state is implicit in the state of woken task (see futex_wait_requeue_pi() for
+ * an example).
+ */
static inline void queue_me(struct futex_q *q, struct futex_hash_bucket *hb)
{
int prio;
@@ -1373,19 +1393,17 @@ static inline void queue_me(struct futex_q *q, struct futex_hash_bucket *hb)
spin_unlock(&hb->lock);
}
-static inline void
-queue_unlock(struct futex_q *q, struct futex_hash_bucket *hb)
-{
- spin_unlock(&hb->lock);
- drop_futex_key_refs(&q->key);
-}
-
-/*
- * queue_me and unqueue_me must be called as a pair, each
- * exactly once. They are called with the hashed spinlock held.
+/**
+ * unqueue_me() - Remove the futex_q from its futex_hash_bucket
+ * @q: The futex_q to unqueue
+ *
+ * The q->lock_ptr must not be held by the caller. A call to unqueue_me() must
+ * be paired with exactly one earlier call to queue_me().
+ *
+ * Returns:
+ * 1 - if the futex_q was still queued (and we removed unqueued it)
+ * 0 - if the futex_q was already removed by the waking thread
*/
-
-/* Return 1 if we were still queued (ie. 0 means we were woken) */
static int unqueue_me(struct futex_q *q)
{
spinlock_t *lock_ptr;
@@ -1638,17 +1656,14 @@ out:
static void futex_wait_queue_me(struct futex_hash_bucket *hb, struct futex_q *q,
struct hrtimer_sleeper *timeout)
{
- queue_me(q, hb);
-
/*
- * There might have been scheduling since the queue_me(), as we
- * cannot hold a spinlock across the get_user() in case it
- * faults, and we cannot just set TASK_INTERRUPTIBLE state when
- * queueing ourselves into the futex hash. This code thus has to
- * rely on the futex_wake() code removing us from hash when it
- * wakes us up.
+ * The task state is guaranteed to be set before another task can
+ * wake it. set_current_state() is implemented using set_mb() and
+ * queue_me() calls spin_unlock() upon completion, both serializing
+ * access to the hash list and forcing another memory barrier.
*/
set_current_state(TASK_INTERRUPTIBLE);
+ queue_me(q, hb);
/* Arm the timer */
if (timeout) {
@@ -1658,8 +1673,8 @@ static void futex_wait_queue_me(struct futex_hash_bucket *hb, struct futex_q *q,
}
/*
- * !plist_node_empty() is safe here without any lock.
- * q.lock_ptr != 0 is not safe, because of ordering against wakeup.
+ * If we have been removed from the hash list, then another task
+ * has tried to wake us, and we can skip the call to schedule().
*/
if (likely(!plist_node_empty(&q->list))) {
/*
@@ -2114,12 +2129,12 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
/**
* futex_wait_requeue_pi() - Wait on uaddr and take uaddr2
- * @uaddr: the futex we initialyl wait on (non-pi)
+ * @uaddr: the futex we initially wait on (non-pi)
* @fshared: whether the futexes are shared (1) or not (0). They must be
* the same type, no requeueing from private to shared, etc.
* @val: the expected value of uaddr
* @abs_time: absolute timeout
- * @bitset: 32 bit wakeup bitset set by userspace, defaults to all.
+ * @bitset: 32 bit wakeup bitset set by userspace, defaults to all
* @clockrt: whether to use CLOCK_REALTIME (1) or CLOCK_MONOTONIC (0)
* @uaddr2: the pi futex we will take prior to returning to user-space
*
@@ -2246,7 +2261,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared,
res = fixup_owner(uaddr2, fshared, &q, !ret);
/*
* If fixup_owner() returned an error, proprogate that. If it
- * acquired the lock, clear our -ETIMEDOUT or -EINTR.
+ * acquired the lock, clear -ETIMEDOUT or -EINTR.
*/
if (res)
ret = (res < 0) ? res : 0;
@@ -2302,9 +2317,9 @@ out:
*/
/**
- * sys_set_robust_list - set the robust-futex list head of a task
- * @head: pointer to the list-head
- * @len: length of the list-head, as userspace expects
+ * sys_set_robust_list() - Set the robust-futex list head of a task
+ * @head: pointer to the list-head
+ * @len: length of the list-head, as userspace expects
*/
SYSCALL_DEFINE2(set_robust_list, struct robust_list_head __user *, head,
size_t, len)
@@ -2323,10 +2338,10 @@ SYSCALL_DEFINE2(set_robust_list, struct robust_list_head __user *, head,
}
/**
- * sys_get_robust_list - get the robust-futex list head of a task
- * @pid: pid of the process [zero for current task]
- * @head_ptr: pointer to a list-head pointer, the kernel fills it in
- * @len_ptr: pointer to a length field, the kernel fills in the header size
+ * sys_get_robust_list() - Get the robust-futex list head of a task
+ * @pid: pid of the process [zero for current task]
+ * @head_ptr: pointer to a list-head pointer, the kernel fills it in
+ * @len_ptr: pointer to a length field, the kernel fills in the header size
*/
SYSCALL_DEFINE3(get_robust_list, int, pid,
struct robust_list_head __user * __user *, head_ptr,
diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig
index 654efd09f6a..70a298d6da7 100644
--- a/kernel/gcov/Kconfig
+++ b/kernel/gcov/Kconfig
@@ -34,7 +34,7 @@ config GCOV_KERNEL
config GCOV_PROFILE_ALL
bool "Profile entire Kernel"
depends on GCOV_KERNEL
- depends on S390 || X86 || (PPC && EXPERIMENTAL)
+ depends on S390 || X86 || (PPC && EXPERIMENTAL) || MICROBLAZE
default n
---help---
This options activates profiling for the entire kernel.
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index c03f221fee4..6d7020490f9 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -48,6 +48,8 @@
#include <asm/uaccess.h>
+#include <trace/events/timer.h>
+
/*
* The timer bases:
*
@@ -442,6 +444,26 @@ static inline void debug_hrtimer_activate(struct hrtimer *timer) { }
static inline void debug_hrtimer_deactivate(struct hrtimer *timer) { }
#endif
+static inline void
+debug_init(struct hrtimer *timer, clockid_t clockid,
+ enum hrtimer_mode mode)
+{
+ debug_hrtimer_init(timer);
+ trace_hrtimer_init(timer, clockid, mode);
+}
+
+static inline void debug_activate(struct hrtimer *timer)
+{
+ debug_hrtimer_activate(timer);
+ trace_hrtimer_start(timer);
+}
+
+static inline void debug_deactivate(struct hrtimer *timer)
+{
+ debug_hrtimer_deactivate(timer);
+ trace_hrtimer_cancel(timer);
+}
+
/* High resolution timer related functions */
#ifdef CONFIG_HIGH_RES_TIMERS
@@ -487,13 +509,14 @@ static inline int hrtimer_hres_active(void)
* next event
* Called with interrupts disabled and base->lock held
*/
-static void hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base)
+static void
+hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal)
{
int i;
struct hrtimer_clock_base *base = cpu_base->clock_base;
- ktime_t expires;
+ ktime_t expires, expires_next;
- cpu_base->expires_next.tv64 = KTIME_MAX;
+ expires_next.tv64 = KTIME_MAX;
for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) {
struct hrtimer *timer;
@@ -509,10 +532,15 @@ static void hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base)
*/
if (expires.tv64 < 0)
expires.tv64 = 0;
- if (expires.tv64 < cpu_base->expires_next.tv64)
- cpu_base->expires_next = expires;
+ if (expires.tv64 < expires_next.tv64)
+ expires_next = expires;
}
+ if (skip_equal && expires_next.tv64 == cpu_base->expires_next.tv64)
+ return;
+
+ cpu_base->expires_next.tv64 = expires_next.tv64;
+
if (cpu_base->expires_next.tv64 != KTIME_MAX)
tick_program_event(cpu_base->expires_next, 1);
}
@@ -595,7 +623,7 @@ static void retrigger_next_event(void *arg)
base->clock_base[CLOCK_REALTIME].offset =
timespec_to_ktime(realtime_offset);
- hrtimer_force_reprogram(base);
+ hrtimer_force_reprogram(base, 0);
spin_unlock(&base->lock);
}
@@ -708,7 +736,8 @@ static int hrtimer_switch_to_hres(void)
static inline int hrtimer_hres_active(void) { return 0; }
static inline int hrtimer_is_hres_enabled(void) { return 0; }
static inline int hrtimer_switch_to_hres(void) { return 0; }
-static inline void hrtimer_force_reprogram(struct hrtimer_cpu_base *base) { }
+static inline void
+hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { }
static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
struct hrtimer_clock_base *base,
int wakeup)
@@ -798,7 +827,7 @@ static int enqueue_hrtimer(struct hrtimer *timer,
struct hrtimer *entry;
int leftmost = 1;
- debug_hrtimer_activate(timer);
+ debug_activate(timer);
/*
* Find the right place in the rbtree:
@@ -851,19 +880,29 @@ static void __remove_hrtimer(struct hrtimer *timer,
struct hrtimer_clock_base *base,
unsigned long newstate, int reprogram)
{
- if (timer->state & HRTIMER_STATE_ENQUEUED) {
- /*
- * Remove the timer from the rbtree and replace the
- * first entry pointer if necessary.
- */
- if (base->first == &timer->node) {
- base->first = rb_next(&timer->node);
- /* Reprogram the clock event device. if enabled */
- if (reprogram && hrtimer_hres_active())
- hrtimer_force_reprogram(base->cpu_base);
+ if (!(timer->state & HRTIMER_STATE_ENQUEUED))
+ goto out;
+
+ /*
+ * Remove the timer from the rbtree and replace the first
+ * entry pointer if necessary.
+ */
+ if (base->first == &timer->node) {
+ base->first = rb_next(&timer->node);
+#ifdef CONFIG_HIGH_RES_TIMERS
+ /* Reprogram the clock event device. if enabled */
+ if (reprogram && hrtimer_hres_active()) {
+ ktime_t expires;
+
+ expires = ktime_sub(hrtimer_get_expires(timer),
+ base->offset);
+ if (base->cpu_base->expires_next.tv64 == expires.tv64)
+ hrtimer_force_reprogram(base->cpu_base, 1);
}
- rb_erase(&timer->node, &base->active);
+#endif
}
+ rb_erase(&timer->node, &base->active);
+out:
timer->state = newstate;
}
@@ -884,7 +923,7 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base)
* reprogramming happens in the interrupt handler. This is a
* rare case and less expensive than a smp call.
*/
- debug_hrtimer_deactivate(timer);
+ debug_deactivate(timer);
timer_stats_hrtimer_clear_start_info(timer);
reprogram = base->cpu_base == &__get_cpu_var(hrtimer_bases);
__remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE,
@@ -1117,7 +1156,7 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
enum hrtimer_mode mode)
{
- debug_hrtimer_init(timer);
+ debug_init(timer, clock_id, mode);
__hrtimer_init(timer, clock_id, mode);
}
EXPORT_SYMBOL_GPL(hrtimer_init);
@@ -1141,7 +1180,7 @@ int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp)
}
EXPORT_SYMBOL_GPL(hrtimer_get_res);
-static void __run_hrtimer(struct hrtimer *timer)
+static void __run_hrtimer(struct hrtimer *timer, ktime_t *now)
{
struct hrtimer_clock_base *base = timer->base;
struct hrtimer_cpu_base *cpu_base = base->cpu_base;
@@ -1150,7 +1189,7 @@ static void __run_hrtimer(struct hrtimer *timer)
WARN_ON(!irqs_disabled());
- debug_hrtimer_deactivate(timer);
+ debug_deactivate(timer);
__remove_hrtimer(timer, base, HRTIMER_STATE_CALLBACK, 0);
timer_stats_account_hrtimer(timer);
fn = timer->function;
@@ -1161,7 +1200,9 @@ static void __run_hrtimer(struct hrtimer *timer)
* the timer base.
*/
spin_unlock(&cpu_base->lock);
+ trace_hrtimer_expire_entry(timer, now);
restart = fn(timer);
+ trace_hrtimer_expire_exit(timer);
spin_lock(&cpu_base->lock);
/*
@@ -1272,7 +1313,7 @@ void hrtimer_interrupt(struct clock_event_device *dev)
break;
}
- __run_hrtimer(timer);
+ __run_hrtimer(timer, &basenow);
}
base++;
}
@@ -1394,7 +1435,7 @@ void hrtimer_run_queues(void)
hrtimer_get_expires_tv64(timer))
break;
- __run_hrtimer(timer);
+ __run_hrtimer(timer, &base->softirq_time);
}
spin_unlock(&cpu_base->lock);
}
@@ -1571,7 +1612,7 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
while ((node = rb_first(&old_base->active))) {
timer = rb_entry(node, struct hrtimer, node);
BUG_ON(hrtimer_callback_running(timer));
- debug_hrtimer_deactivate(timer);
+ debug_deactivate(timer);
/*
* Mark it as STATE_MIGRATE not INACTIVE otherwise the
diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index 022a4927b78..d4e84174740 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -171,12 +171,12 @@ static unsigned long timeout_jiffies(unsigned long timeout)
* Process updating of timeout sysctl
*/
int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
- struct file *filp, void __user *buffer,
+ void __user *buffer,
size_t *lenp, loff_t *ppos)
{
int ret;
- ret = proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos);
+ ret = proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
if (ret || !write)
goto out;
diff --git a/kernel/itimer.c b/kernel/itimer.c
index 58762f7077e..b03451ede52 100644
--- a/kernel/itimer.c
+++ b/kernel/itimer.c
@@ -12,6 +12,7 @@
#include <linux/time.h>
#include <linux/posix-timers.h>
#include <linux/hrtimer.h>
+#include <trace/events/timer.h>
#include <asm/uaccess.h>
@@ -41,10 +42,43 @@ static struct timeval itimer_get_remtime(struct hrtimer *timer)
return ktime_to_timeval(rem);
}
+static void get_cpu_itimer(struct task_struct *tsk, unsigned int clock_id,
+ struct itimerval *const value)
+{
+ cputime_t cval, cinterval;
+ struct cpu_itimer *it = &tsk->signal->it[clock_id];
+
+ spin_lock_irq(&tsk->sighand->siglock);
+
+ cval = it->expires;
+ cinterval = it->incr;
+ if (!cputime_eq(cval, cputime_zero)) {
+ struct task_cputime cputime;
+ cputime_t t;
+
+ thread_group_cputimer(tsk, &cputime);
+ if (clock_id == CPUCLOCK_PROF)
+ t = cputime_add(cputime.utime, cputime.stime);
+ else
+ /* CPUCLOCK_VIRT */
+ t = cputime.utime;
+
+ if (cputime_le(cval, t))
+ /* about to fire */
+ cval = cputime_one_jiffy;
+ else
+ cval = cputime_sub(cval, t);
+ }
+
+ spin_unlock_irq(&tsk->sighand->siglock);
+
+ cputime_to_timeval(cval, &value->it_value);
+ cputime_to_timeval(cinterval, &value->it_interval);
+}
+
int do_getitimer(int which, struct itimerval *value)
{
struct task_struct *tsk = current;
- cputime_t cinterval, cval;
switch (which) {
case ITIMER_REAL:
@@ -55,44 +89,10 @@ int do_getitimer(int which, struct itimerval *value)
spin_unlock_irq(&tsk->sighand->siglock);
break;
case ITIMER_VIRTUAL:
- spin_lock_irq(&tsk->sighand->siglock);
- cval = tsk->signal->it_virt_expires;
- cinterval = tsk->signal->it_virt_incr;
- if (!cputime_eq(cval, cputime_zero)) {
- struct task_cputime cputime;
- cputime_t utime;
-
- thread_group_cputimer(tsk, &cputime);
- utime = cputime.utime;
- if (cputime_le(cval, utime)) { /* about to fire */
- cval = jiffies_to_cputime(1);
- } else {
- cval = cputime_sub(cval, utime);
- }
- }
- spin_unlock_irq(&tsk->sighand->siglock);
- cputime_to_timeval(cval, &value->it_value);
- cputime_to_timeval(cinterval, &value->it_interval);
+ get_cpu_itimer(tsk, CPUCLOCK_VIRT, value);
break;
case ITIMER_PROF:
- spin_lock_irq(&tsk->sighand->siglock);
- cval = tsk->signal->it_prof_expires;
- cinterval = tsk->signal->it_prof_incr;
- if (!cputime_eq(cval, cputime_zero)) {
- struct task_cputime times;
- cputime_t ptime;
-
- thread_group_cputimer(tsk, &times);
- ptime = cputime_add(times.utime, times.stime);
- if (cputime_le(cval, ptime)) { /* about to fire */
- cval = jiffies_to_cputime(1);
- } else {
- cval = cputime_sub(cval, ptime);
- }
- }
- spin_unlock_irq(&tsk->sighand->siglock);
- cputime_to_timeval(cval, &value->it_value);
- cputime_to_timeval(cinterval, &value->it_interval);
+ get_cpu_itimer(tsk, CPUCLOCK_PROF, value);
break;
default:
return(-EINVAL);
@@ -123,11 +123,62 @@ enum hrtimer_restart it_real_fn(struct hrtimer *timer)
struct signal_struct *sig =
container_of(timer, struct signal_struct, real_timer);
+ trace_itimer_expire(ITIMER_REAL, sig->leader_pid, 0);
kill_pid_info(SIGALRM, SEND_SIG_PRIV, sig->leader_pid);
return HRTIMER_NORESTART;
}
+static inline u32 cputime_sub_ns(cputime_t ct, s64 real_ns)
+{
+ struct timespec ts;
+ s64 cpu_ns;
+
+ cputime_to_timespec(ct, &ts);
+ cpu_ns = timespec_to_ns(&ts);
+
+ return (cpu_ns <= real_ns) ? 0 : cpu_ns - real_ns;
+}
+
+static void set_cpu_itimer(struct task_struct *tsk, unsigned int clock_id,
+ const struct itimerval *const value,
+ struct itimerval *const ovalue)
+{
+ cputime_t cval, nval, cinterval, ninterval;
+ s64 ns_ninterval, ns_nval;
+ struct cpu_itimer *it = &tsk->signal->it[clock_id];
+
+ nval = timeval_to_cputime(&value->it_value);
+ ns_nval = timeval_to_ns(&value->it_value);
+ ninterval = timeval_to_cputime(&value->it_interval);
+ ns_ninterval = timeval_to_ns(&value->it_interval);
+
+ it->incr_error = cputime_sub_ns(ninterval, ns_ninterval);
+ it->error = cputime_sub_ns(nval, ns_nval);
+
+ spin_lock_irq(&tsk->sighand->siglock);
+
+ cval = it->expires;
+ cinterval = it->incr;
+ if (!cputime_eq(cval, cputime_zero) ||
+ !cputime_eq(nval, cputime_zero)) {
+ if (cputime_gt(nval, cputime_zero))
+ nval = cputime_add(nval, cputime_one_jiffy);
+ set_process_cpu_timer(tsk, clock_id, &nval, &cval);
+ }
+ it->expires = nval;
+ it->incr = ninterval;
+ trace_itimer_state(clock_id == CPUCLOCK_VIRT ?
+ ITIMER_VIRTUAL : ITIMER_PROF, value, nval);
+
+ spin_unlock_irq(&tsk->sighand->siglock);
+
+ if (ovalue) {
+ cputime_to_timeval(cval, &ovalue->it_value);
+ cputime_to_timeval(cinterval, &ovalue->it_interval);
+ }
+}
+
/*
* Returns true if the timeval is in canonical form
*/
@@ -139,7 +190,6 @@ int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue)
struct task_struct *tsk = current;
struct hrtimer *timer;
ktime_t expires;
- cputime_t cval, cinterval, nval, ninterval;
/*
* Validate the timevals in value.
@@ -171,51 +221,14 @@ again:
} else
tsk->signal->it_real_incr.tv64 = 0;
+ trace_itimer_state(ITIMER_REAL, value, 0);
spin_unlock_irq(&tsk->sighand->siglock);
break;
case ITIMER_VIRTUAL:
- nval = timeval_to_cputime(&value->it_value);
- ninterval = timeval_to_cputime(&value->it_interval);
- spin_lock_irq(&tsk->sighand->siglock);
- cval = tsk->signal->it_virt_expires;
- cinterval = tsk->signal->it_virt_incr;
- if (!cputime_eq(cval, cputime_zero) ||
- !cputime_eq(nval, cputime_zero)) {
- if (cputime_gt(nval, cputime_zero))
- nval = cputime_add(nval,
- jiffies_to_cputime(1));
- set_process_cpu_timer(tsk, CPUCLOCK_VIRT,
- &nval, &cval);
- }
- tsk->signal->it_virt_expires = nval;
- tsk->signal->it_virt_incr = ninterval;
- spin_unlock_irq(&tsk->sighand->siglock);
- if (ovalue) {
- cputime_to_timeval(cval, &ovalue->it_value);
- cputime_to_timeval(cinterval, &ovalue->it_interval);
- }
+ set_cpu_itimer(tsk, CPUCLOCK_VIRT, value, ovalue);
break;
case ITIMER_PROF:
- nval = timeval_to_cputime(&value->it_value);
- ninterval = timeval_to_cputime(&value->it_interval);
- spin_lock_irq(&tsk->sighand->siglock);
- cval = tsk->signal->it_prof_expires;
- cinterval = tsk->signal->it_prof_incr;
- if (!cputime_eq(cval, cputime_zero) ||
- !cputime_eq(nval, cputime_zero)) {
- if (cputime_gt(nval, cputime_zero))
- nval = cputime_add(nval,
- jiffies_to_cputime(1));
- set_process_cpu_timer(tsk, CPUCLOCK_PROF,
- &nval, &cval);
- }
- tsk->signal->it_prof_expires = nval;
- tsk->signal->it_prof_incr = ninterval;
- spin_unlock_irq(&tsk->sighand->siglock);
- if (ovalue) {
- cputime_to_timeval(cval, &ovalue->it_value);
- cputime_to_timeval(cinterval, &ovalue->it_interval);
- }
+ set_cpu_itimer(tsk, CPUCLOCK_PROF, value, ovalue);
break;
default:
return -EINVAL;
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 3a29dbe7898..8b6b8b697c6 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -59,7 +59,8 @@ static inline int is_kernel_inittext(unsigned long addr)
static inline int is_kernel_text(unsigned long addr)
{
- if (addr >= (unsigned long)_stext && addr <= (unsigned long)_etext)
+ if ((addr >= (unsigned long)_stext && addr <= (unsigned long)_etext) ||
+ arch_is_kernel_text(addr))
return 1;
return in_gate_area_no_task(addr);
}
diff --git a/kernel/kfifo.c b/kernel/kfifo.c
index 26539e3228e..3765ff3c1bb 100644
--- a/kernel/kfifo.c
+++ b/kernel/kfifo.c
@@ -117,7 +117,7 @@ EXPORT_SYMBOL(kfifo_free);
* writer, you don't need extra locking to use these functions.
*/
unsigned int __kfifo_put(struct kfifo *fifo,
- unsigned char *buffer, unsigned int len)
+ const unsigned char *buffer, unsigned int len)
{
unsigned int l;
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index ef177d653b2..5240d75f4c6 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1321,7 +1321,7 @@ static int __kprobes show_kprobe_addr(struct seq_file *pi, void *v)
return 0;
}
-static struct seq_operations kprobes_seq_ops = {
+static const struct seq_operations kprobes_seq_ops = {
.start = kprobe_seq_start,
.next = kprobe_seq_next,
.stop = kprobe_seq_stop,
@@ -1333,7 +1333,7 @@ static int __kprobes kprobes_open(struct inode *inode, struct file *filp)
return seq_open(filp, &kprobes_seq_ops);
}
-static struct file_operations debugfs_kprobes_operations = {
+static const struct file_operations debugfs_kprobes_operations = {
.open = kprobes_open,
.read = seq_read,
.llseek = seq_lseek,
@@ -1515,7 +1515,7 @@ static ssize_t write_enabled_file_bool(struct file *file,
return count;
}
-static struct file_operations fops_kp = {
+static const struct file_operations fops_kp = {
.read = read_enabled_file_bool,
.write = write_enabled_file_bool,
};
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index f74d2d7aa60..3815ac1d58b 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -578,6 +578,9 @@ static int static_obj(void *obj)
if ((addr >= start) && (addr < end))
return 1;
+ if (arch_is_kernel_data(addr))
+ return 1;
+
#ifdef CONFIG_SMP
/*
* percpu var?
diff --git a/kernel/lockdep_proc.c b/kernel/lockdep_proc.c
index d4b3dbc79fd..d4aba4f3584 100644
--- a/kernel/lockdep_proc.c
+++ b/kernel/lockdep_proc.c
@@ -594,7 +594,7 @@ static int ls_show(struct seq_file *m, void *v)
return 0;
}
-static struct seq_operations lockstat_ops = {
+static const struct seq_operations lockstat_ops = {
.start = ls_start,
.next = ls_next,
.stop = ls_stop,
diff --git a/kernel/marker.c b/kernel/marker.c
deleted file mode 100644
index ea54f264786..00000000000
--- a/kernel/marker.c
+++ /dev/null
@@ -1,930 +0,0 @@
-/*
- * Copyright (C) 2007 Mathieu Desnoyers
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- */
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/types.h>
-#include <linux/jhash.h>
-#include <linux/list.h>
-#include <linux/rcupdate.h>
-#include <linux/marker.h>
-#include <linux/err.h>
-#include <linux/slab.h>
-
-extern struct marker __start___markers[];
-extern struct marker __stop___markers[];
-
-/* Set to 1 to enable marker debug output */
-static const int marker_debug;
-
-/*
- * markers_mutex nests inside module_mutex. Markers mutex protects the builtin
- * and module markers and the hash table.
- */
-static DEFINE_MUTEX(markers_mutex);
-
-/*
- * Marker hash table, containing the active markers.
- * Protected by module_mutex.
- */
-#define MARKER_HASH_BITS 6
-#define MARKER_TABLE_SIZE (1 << MARKER_HASH_BITS)
-static struct hlist_head marker_table[MARKER_TABLE_SIZE];
-
-/*
- * Note about RCU :
- * It is used to make sure every handler has finished using its private data
- * between two consecutive operation (add or remove) on a given marker. It is
- * also used to delay the free of multiple probes array until a quiescent state
- * is reached.
- * marker entries modifications are protected by the markers_mutex.
- */
-struct marker_entry {
- struct hlist_node hlist;
- char *format;
- /* Probe wrapper */
- void (*call)(const struct marker *mdata, void *call_private, ...);
- struct marker_probe_closure single;
- struct marker_probe_closure *multi;
- int refcount; /* Number of times armed. 0 if disarmed. */
- struct rcu_head rcu;
- void *oldptr;
- int rcu_pending;
- unsigned char ptype:1;
- unsigned char format_allocated:1;
- char name[0]; /* Contains name'\0'format'\0' */
-};
-
-/**
- * __mark_empty_function - Empty probe callback
- * @probe_private: probe private data
- * @call_private: call site private data
- * @fmt: format string
- * @...: variable argument list
- *
- * Empty callback provided as a probe to the markers. By providing this to a
- * disabled marker, we make sure the execution flow is always valid even
- * though the function pointer change and the marker enabling are two distinct
- * operations that modifies the execution flow of preemptible code.
- */
-notrace void __mark_empty_function(void *probe_private, void *call_private,
- const char *fmt, va_list *args)
-{
-}
-EXPORT_SYMBOL_GPL(__mark_empty_function);
-
-/*
- * marker_probe_cb Callback that prepares the variable argument list for probes.
- * @mdata: pointer of type struct marker
- * @call_private: caller site private data
- * @...: Variable argument list.
- *
- * Since we do not use "typical" pointer based RCU in the 1 argument case, we
- * need to put a full smp_rmb() in this branch. This is why we do not use
- * rcu_dereference() for the pointer read.
- */
-notrace void marker_probe_cb(const struct marker *mdata,
- void *call_private, ...)
-{
- va_list args;
- char ptype;
-
- /*
- * rcu_read_lock_sched does two things : disabling preemption to make
- * sure the teardown of the callbacks can be done correctly when they
- * are in modules and they insure RCU read coherency.
- */
- rcu_read_lock_sched_notrace();
- ptype = mdata->ptype;
- if (likely(!ptype)) {
- marker_probe_func *func;
- /* Must read the ptype before ptr. They are not data dependant,
- * so we put an explicit smp_rmb() here. */
- smp_rmb();
- func = mdata->single.func;
- /* Must read the ptr before private data. They are not data
- * dependant, so we put an explicit smp_rmb() here. */
- smp_rmb();
- va_start(args, call_private);
- func(mdata->single.probe_private, call_private, mdata->format,
- &args);
- va_end(args);
- } else {
- struct marker_probe_closure *multi;
- int i;
- /*
- * Read mdata->ptype before mdata->multi.
- */
- smp_rmb();
- multi = mdata->multi;
- /*
- * multi points to an array, therefore accessing the array
- * depends on reading multi. However, even in this case,
- * we must insure that the pointer is read _before_ the array
- * data. Same as rcu_dereference, but we need a full smp_rmb()
- * in the fast path, so put the explicit barrier here.
- */
- smp_read_barrier_depends();
- for (i = 0; multi[i].func; i++) {
- va_start(args, call_private);
- multi[i].func(multi[i].probe_private, call_private,
- mdata->format, &args);
- va_end(args);
- }
- }
- rcu_read_unlock_sched_notrace();
-}
-EXPORT_SYMBOL_GPL(marker_probe_cb);
-
-/*
- * marker_probe_cb Callback that does not prepare the variable argument list.
- * @mdata: pointer of type struct marker
- * @call_private: caller site private data
- * @...: Variable argument list.
- *
- * Should be connected to markers "MARK_NOARGS".
- */
-static notrace void marker_probe_cb_noarg(const struct marker *mdata,
- void *call_private, ...)
-{
- va_list args; /* not initialized */
- char ptype;
-
- rcu_read_lock_sched_notrace();
- ptype = mdata->ptype;
- if (likely(!ptype)) {
- marker_probe_func *func;
- /* Must read the ptype before ptr. They are not data dependant,
- * so we put an explicit smp_rmb() here. */
- smp_rmb();
- func = mdata->single.func;
- /* Must read the ptr before private data. They are not data
- * dependant, so we put an explicit smp_rmb() here. */
- smp_rmb();
- func(mdata->single.probe_private, call_private, mdata->format,
- &args);
- } else {
- struct marker_probe_closure *multi;
- int i;
- /*
- * Read mdata->ptype before mdata->multi.
- */
- smp_rmb();
- multi = mdata->multi;
- /*
- * multi points to an array, therefore accessing the array
- * depends on reading multi. However, even in this case,
- * we must insure that the pointer is read _before_ the array
- * data. Same as rcu_dereference, but we need a full smp_rmb()
- * in the fast path, so put the explicit barrier here.
- */
- smp_read_barrier_depends();
- for (i = 0; multi[i].func; i++)
- multi[i].func(multi[i].probe_private, call_private,
- mdata->format, &args);
- }
- rcu_read_unlock_sched_notrace();
-}
-
-static void free_old_closure(struct rcu_head *head)
-{
- struct marker_entry *entry = container_of(head,
- struct marker_entry, rcu);
- kfree(entry->oldptr);
- /* Make sure we free the data before setting the pending flag to 0 */
- smp_wmb();
- entry->rcu_pending = 0;
-}
-
-static void debug_print_probes(struct marker_entry *entry)
-{
- int i;
-
- if (!marker_debug)
- return;
-
- if (!entry->ptype) {
- printk(KERN_DEBUG "Single probe : %p %p\n",
- entry->single.func,
- entry->single.probe_private);
- } else {
- for (i = 0; entry->multi[i].func; i++)
- printk(KERN_DEBUG "Multi probe %d : %p %p\n", i,
- entry->multi[i].func,
- entry->multi[i].probe_private);
- }
-}
-
-static struct marker_probe_closure *
-marker_entry_add_probe(struct marker_entry *entry,
- marker_probe_func *probe, void *probe_private)
-{
- int nr_probes = 0;
- struct marker_probe_closure *old, *new;
-
- WARN_ON(!probe);
-
- debug_print_probes(entry);
- old = entry->multi;
- if (!entry->ptype) {
- if (entry->single.func == probe &&
- entry->single.probe_private == probe_private)
- return ERR_PTR(-EBUSY);
- if (entry->single.func == __mark_empty_function) {
- /* 0 -> 1 probes */
- entry->single.func = probe;
- entry->single.probe_private = probe_private;
- entry->refcount = 1;
- entry->ptype = 0;
- debug_print_probes(entry);
- return NULL;
- } else {
- /* 1 -> 2 probes */
- nr_probes = 1;
- old = NULL;
- }
- } else {
- /* (N -> N+1), (N != 0, 1) probes */
- for (nr_probes = 0; old[nr_probes].func; nr_probes++)
- if (old[nr_probes].func == probe
- && old[nr_probes].probe_private
- == probe_private)
- return ERR_PTR(-EBUSY);
- }
- /* + 2 : one for new probe, one for NULL func */
- new = kzalloc((nr_probes + 2) * sizeof(struct marker_probe_closure),
- GFP_KERNEL);
- if (new == NULL)
- return ERR_PTR(-ENOMEM);
- if (!old)
- new[0] = entry->single;
- else
- memcpy(new, old,
- nr_probes * sizeof(struct marker_probe_closure));
- new[nr_probes].func = probe;
- new[nr_probes].probe_private = probe_private;
- entry->refcount = nr_probes + 1;
- entry->multi = new;
- entry->ptype = 1;
- debug_print_probes(entry);
- return old;
-}
-
-static struct marker_probe_closure *
-marker_entry_remove_probe(struct marker_entry *entry,
- marker_probe_func *probe, void *probe_private)
-{
- int nr_probes = 0, nr_del = 0, i;
- struct marker_probe_closure *old, *new;
-
- old = entry->multi;
-
- debug_print_probes(entry);
- if (!entry->ptype) {
- /* 0 -> N is an error */
- WARN_ON(entry->single.func == __mark_empty_function);
- /* 1 -> 0 probes */
- WARN_ON(probe && entry->single.func != probe);
- WARN_ON(entry->single.probe_private != probe_private);
- entry->single.func = __mark_empty_function;
- entry->refcount = 0;
- entry->ptype = 0;
- debug_print_probes(entry);
- return NULL;
- } else {
- /* (N -> M), (N > 1, M >= 0) probes */
- for (nr_probes = 0; old[nr_probes].func; nr_probes++) {
- if ((!probe || old[nr_probes].func == probe)
- && old[nr_probes].probe_private
- == probe_private)
- nr_del++;
- }
- }
-
- if (nr_probes - nr_del == 0) {
- /* N -> 0, (N > 1) */
- entry->single.func = __mark_empty_function;
- entry->refcount = 0;
- entry->ptype = 0;
- } else if (nr_probes - nr_del == 1) {
- /* N -> 1, (N > 1) */
- for (i = 0; old[i].func; i++)
- if ((probe && old[i].func != probe) ||
- old[i].probe_private != probe_private)
- entry->single = old[i];
- entry->refcount = 1;
- entry->ptype = 0;
- } else {
- int j = 0;
- /* N -> M, (N > 1, M > 1) */
- /* + 1 for NULL */
- new = kzalloc((nr_probes - nr_del + 1)
- * sizeof(struct marker_probe_closure), GFP_KERNEL);
- if (new == NULL)
- return ERR_PTR(-ENOMEM);
- for (i = 0; old[i].func; i++)
- if ((probe && old[i].func != probe) ||
- old[i].probe_private != probe_private)
- new[j++] = old[i];
- entry->refcount = nr_probes - nr_del;
- entry->ptype = 1;
- entry->multi = new;
- }
- debug_print_probes(entry);
- return old;
-}
-
-/*
- * Get marker if the marker is present in the marker hash table.
- * Must be called with markers_mutex held.
- * Returns NULL if not present.
- */
-static struct marker_entry *get_marker(const char *name)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct marker_entry *e;
- u32 hash = jhash(name, strlen(name), 0);
-
- head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
- hlist_for_each_entry(e, node, head, hlist) {
- if (!strcmp(name, e->name))
- return e;
- }
- return NULL;
-}
-
-/*
- * Add the marker to the marker hash table. Must be called with markers_mutex
- * held.
- */
-static struct marker_entry *add_marker(const char *name, const char *format)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct marker_entry *e;
- size_t name_len = strlen(name) + 1;
- size_t format_len = 0;
- u32 hash = jhash(name, name_len-1, 0);
-
- if (format)
- format_len = strlen(format) + 1;
- head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
- hlist_for_each_entry(e, node, head, hlist) {
- if (!strcmp(name, e->name)) {
- printk(KERN_NOTICE
- "Marker %s busy\n", name);
- return ERR_PTR(-EBUSY); /* Already there */
- }
- }
- /*
- * Using kmalloc here to allocate a variable length element. Could
- * cause some memory fragmentation if overused.
- */
- e = kmalloc(sizeof(struct marker_entry) + name_len + format_len,
- GFP_KERNEL);
- if (!e)
- return ERR_PTR(-ENOMEM);
- memcpy(&e->name[0], name, name_len);
- if (format) {
- e->format = &e->name[name_len];
- memcpy(e->format, format, format_len);
- if (strcmp(e->format, MARK_NOARGS) == 0)
- e->call = marker_probe_cb_noarg;
- else
- e->call = marker_probe_cb;
- trace_mark(core_marker_format, "name %s format %s",
- e->name, e->format);
- } else {
- e->format = NULL;
- e->call = marker_probe_cb;
- }
- e->single.func = __mark_empty_function;
- e->single.probe_private = NULL;
- e->multi = NULL;
- e->ptype = 0;
- e->format_allocated = 0;
- e->refcount = 0;
- e->rcu_pending = 0;
- hlist_add_head(&e->hlist, head);
- return e;
-}
-
-/*
- * Remove the marker from the marker hash table. Must be called with mutex_lock
- * held.
- */
-static int remove_marker(const char *name)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct marker_entry *e;
- int found = 0;
- size_t len = strlen(name) + 1;
- u32 hash = jhash(name, len-1, 0);
-
- head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
- hlist_for_each_entry(e, node, head, hlist) {
- if (!strcmp(name, e->name)) {
- found = 1;
- break;
- }
- }
- if (!found)
- return -ENOENT;
- if (e->single.func != __mark_empty_function)
- return -EBUSY;
- hlist_del(&e->hlist);
- if (e->format_allocated)
- kfree(e->format);
- /* Make sure the call_rcu has been executed */
- if (e->rcu_pending)
- rcu_barrier_sched();
- kfree(e);
- return 0;
-}
-
-/*
- * Set the mark_entry format to the format found in the element.
- */
-static int marker_set_format(struct marker_entry *entry, const char *format)
-{
- entry->format = kstrdup(format, GFP_KERNEL);
- if (!entry->format)
- return -ENOMEM;
- entry->format_allocated = 1;
-
- trace_mark(core_marker_format, "name %s format %s",
- entry->name, entry->format);
- return 0;
-}
-
-/*
- * Sets the probe callback corresponding to one marker.
- */
-static int set_marker(struct marker_entry *entry, struct marker *elem,
- int active)
-{
- int ret = 0;
- WARN_ON(strcmp(entry->name, elem->name) != 0);
-
- if (entry->format) {
- if (strcmp(entry->format, elem->format) != 0) {
- printk(KERN_NOTICE
- "Format mismatch for probe %s "
- "(%s), marker (%s)\n",
- entry->name,
- entry->format,
- elem->format);
- return -EPERM;
- }
- } else {
- ret = marker_set_format(entry, elem->format);
- if (ret)
- return ret;
- }
-
- /*
- * probe_cb setup (statically known) is done here. It is
- * asynchronous with the rest of execution, therefore we only
- * pass from a "safe" callback (with argument) to an "unsafe"
- * callback (does not set arguments).
- */
- elem->call = entry->call;
- /*
- * Sanity check :
- * We only update the single probe private data when the ptr is
- * set to a _non_ single probe! (0 -> 1 and N -> 1, N != 1)
- */
- WARN_ON(elem->single.func != __mark_empty_function
- && elem->single.probe_private != entry->single.probe_private
- && !elem->ptype);
- elem->single.probe_private = entry->single.probe_private;
- /*
- * Make sure the private data is valid when we update the
- * single probe ptr.
- */
- smp_wmb();
- elem->single.func = entry->single.func;
- /*
- * We also make sure that the new probe callbacks array is consistent
- * before setting a pointer to it.
- */
- rcu_assign_pointer(elem->multi, entry->multi);
- /*
- * Update the function or multi probe array pointer before setting the
- * ptype.
- */
- smp_wmb();
- elem->ptype = entry->ptype;
-
- if (elem->tp_name && (active ^ elem->state)) {
- WARN_ON(!elem->tp_cb);
- /*
- * It is ok to directly call the probe registration because type
- * checking has been done in the __trace_mark_tp() macro.
- */
-
- if (active) {
- /*
- * try_module_get should always succeed because we hold
- * lock_module() to get the tp_cb address.
- */
- ret = try_module_get(__module_text_address(
- (unsigned long)elem->tp_cb));
- BUG_ON(!ret);
- ret = tracepoint_probe_register_noupdate(
- elem->tp_name,
- elem->tp_cb);
- } else {
- ret = tracepoint_probe_unregister_noupdate(
- elem->tp_name,
- elem->tp_cb);
- /*
- * tracepoint_probe_update_all() must be called
- * before the module containing tp_cb is unloaded.
- */
- module_put(__module_text_address(
- (unsigned long)elem->tp_cb));
- }
- }
- elem->state = active;
-
- return ret;
-}
-
-/*
- * Disable a marker and its probe callback.
- * Note: only waiting an RCU period after setting elem->call to the empty
- * function insures that the original callback is not used anymore. This insured
- * by rcu_read_lock_sched around the call site.
- */
-static void disable_marker(struct marker *elem)
-{
- int ret;
-
- /* leave "call" as is. It is known statically. */
- if (elem->tp_name && elem->state) {
- WARN_ON(!elem->tp_cb);
- /*
- * It is ok to directly call the probe registration because type
- * checking has been done in the __trace_mark_tp() macro.
- */
- ret = tracepoint_probe_unregister_noupdate(elem->tp_name,
- elem->tp_cb);
- WARN_ON(ret);
- /*
- * tracepoint_probe_update_all() must be called
- * before the module containing tp_cb is unloaded.
- */
- module_put(__module_text_address((unsigned long)elem->tp_cb));
- }
- elem->state = 0;
- elem->single.func = __mark_empty_function;
- /* Update the function before setting the ptype */
- smp_wmb();
- elem->ptype = 0; /* single probe */
- /*
- * Leave the private data and id there, because removal is racy and
- * should be done only after an RCU period. These are never used until
- * the next initialization anyway.
- */
-}
-
-/**
- * marker_update_probe_range - Update a probe range
- * @begin: beginning of the range
- * @end: end of the range
- *
- * Updates the probe callback corresponding to a range of markers.
- */
-void marker_update_probe_range(struct marker *begin,
- struct marker *end)
-{
- struct marker *iter;
- struct marker_entry *mark_entry;
-
- mutex_lock(&markers_mutex);
- for (iter = begin; iter < end; iter++) {
- mark_entry = get_marker(iter->name);
- if (mark_entry) {
- set_marker(mark_entry, iter, !!mark_entry->refcount);
- /*
- * ignore error, continue
- */
- } else {
- disable_marker(iter);
- }
- }
- mutex_unlock(&markers_mutex);
-}
-
-/*
- * Update probes, removing the faulty probes.
- *
- * Internal callback only changed before the first probe is connected to it.
- * Single probe private data can only be changed on 0 -> 1 and 2 -> 1
- * transitions. All other transitions will leave the old private data valid.
- * This makes the non-atomicity of the callback/private data updates valid.
- *
- * "special case" updates :
- * 0 -> 1 callback
- * 1 -> 0 callback
- * 1 -> 2 callbacks
- * 2 -> 1 callbacks
- * Other updates all behave the same, just like the 2 -> 3 or 3 -> 2 updates.
- * Site effect : marker_set_format may delete the marker entry (creating a
- * replacement).
- */
-static void marker_update_probes(void)
-{
- /* Core kernel markers */
- marker_update_probe_range(__start___markers, __stop___markers);
- /* Markers in modules. */
- module_update_markers();
- tracepoint_probe_update_all();
-}
-
-/**
- * marker_probe_register - Connect a probe to a marker
- * @name: marker name
- * @format: format string
- * @probe: probe handler
- * @probe_private: probe private data
- *
- * private data must be a valid allocated memory address, or NULL.
- * Returns 0 if ok, error value on error.
- * The probe address must at least be aligned on the architecture pointer size.
- */
-int marker_probe_register(const char *name, const char *format,
- marker_probe_func *probe, void *probe_private)
-{
- struct marker_entry *entry;
- int ret = 0;
- struct marker_probe_closure *old;
-
- mutex_lock(&markers_mutex);
- entry = get_marker(name);
- if (!entry) {
- entry = add_marker(name, format);
- if (IS_ERR(entry))
- ret = PTR_ERR(entry);
- } else if (format) {
- if (!entry->format)
- ret = marker_set_format(entry, format);
- else if (strcmp(entry->format, format))
- ret = -EPERM;
- }
- if (ret)
- goto end;
-
- /*
- * If we detect that a call_rcu is pending for this marker,
- * make sure it's executed now.
- */
- if (entry->rcu_pending)
- rcu_barrier_sched();
- old = marker_entry_add_probe(entry, probe, probe_private);
- if (IS_ERR(old)) {
- ret = PTR_ERR(old);
- goto end;
- }
- mutex_unlock(&markers_mutex);
- marker_update_probes();
- mutex_lock(&markers_mutex);
- entry = get_marker(name);
- if (!entry)
- goto end;
- if (entry->rcu_pending)
- rcu_barrier_sched();
- entry->oldptr = old;
- entry->rcu_pending = 1;
- /* write rcu_pending before calling the RCU callback */
- smp_wmb();
- call_rcu_sched(&entry->rcu, free_old_closure);
-end:
- mutex_unlock(&markers_mutex);
- return ret;
-}
-EXPORT_SYMBOL_GPL(marker_probe_register);
-
-/**
- * marker_probe_unregister - Disconnect a probe from a marker
- * @name: marker name
- * @probe: probe function pointer
- * @probe_private: probe private data
- *
- * Returns the private data given to marker_probe_register, or an ERR_PTR().
- * We do not need to call a synchronize_sched to make sure the probes have
- * finished running before doing a module unload, because the module unload
- * itself uses stop_machine(), which insures that every preempt disabled section
- * have finished.
- */
-int marker_probe_unregister(const char *name,
- marker_probe_func *probe, void *probe_private)
-{
- struct marker_entry *entry;
- struct marker_probe_closure *old;
- int ret = -ENOENT;
-
- mutex_lock(&markers_mutex);
- entry = get_marker(name);
- if (!entry)
- goto end;
- if (entry->rcu_pending)
- rcu_barrier_sched();
- old = marker_entry_remove_probe(entry, probe, probe_private);
- mutex_unlock(&markers_mutex);
- marker_update_probes();
- mutex_lock(&markers_mutex);
- entry = get_marker(name);
- if (!entry)
- goto end;
- if (entry->rcu_pending)
- rcu_barrier_sched();
- entry->oldptr = old;
- entry->rcu_pending = 1;
- /* write rcu_pending before calling the RCU callback */
- smp_wmb();
- call_rcu_sched(&entry->rcu, free_old_closure);
- remove_marker(name); /* Ignore busy error message */
- ret = 0;
-end:
- mutex_unlock(&markers_mutex);
- return ret;
-}
-EXPORT_SYMBOL_GPL(marker_probe_unregister);
-
-static struct marker_entry *
-get_marker_from_private_data(marker_probe_func *probe, void *probe_private)
-{
- struct marker_entry *entry;
- unsigned int i;
- struct hlist_head *head;
- struct hlist_node *node;
-
- for (i = 0; i < MARKER_TABLE_SIZE; i++) {
- head = &marker_table[i];
- hlist_for_each_entry(entry, node, head, hlist) {
- if (!entry->ptype) {
- if (entry->single.func == probe
- && entry->single.probe_private
- == probe_private)
- return entry;
- } else {
- struct marker_probe_closure *closure;
- closure = entry->multi;
- for (i = 0; closure[i].func; i++) {
- if (closure[i].func == probe &&
- closure[i].probe_private
- == probe_private)
- return entry;
- }
- }
- }
- }
- return NULL;
-}
-
-/**
- * marker_probe_unregister_private_data - Disconnect a probe from a marker
- * @probe: probe function
- * @probe_private: probe private data
- *
- * Unregister a probe by providing the registered private data.
- * Only removes the first marker found in hash table.
- * Return 0 on success or error value.
- * We do not need to call a synchronize_sched to make sure the probes have
- * finished running before doing a module unload, because the module unload
- * itself uses stop_machine(), which insures that every preempt disabled section
- * have finished.
- */
-int marker_probe_unregister_private_data(marker_probe_func *probe,
- void *probe_private)
-{
- struct marker_entry *entry;
- int ret = 0;
- struct marker_probe_closure *old;
-
- mutex_lock(&markers_mutex);
- entry = get_marker_from_private_data(probe, probe_private);
- if (!entry) {
- ret = -ENOENT;
- goto end;
- }
- if (entry->rcu_pending)
- rcu_barrier_sched();
- old = marker_entry_remove_probe(entry, NULL, probe_private);
- mutex_unlock(&markers_mutex);
- marker_update_probes();
- mutex_lock(&markers_mutex);
- entry = get_marker_from_private_data(probe, probe_private);
- if (!entry)
- goto end;
- if (entry->rcu_pending)
- rcu_barrier_sched();
- entry->oldptr = old;
- entry->rcu_pending = 1;
- /* write rcu_pending before calling the RCU callback */
- smp_wmb();
- call_rcu_sched(&entry->rcu, free_old_closure);
- remove_marker(entry->name); /* Ignore busy error message */
-end:
- mutex_unlock(&markers_mutex);
- return ret;
-}
-EXPORT_SYMBOL_GPL(marker_probe_unregister_private_data);
-
-/**
- * marker_get_private_data - Get a marker's probe private data
- * @name: marker name
- * @probe: probe to match
- * @num: get the nth matching probe's private data
- *
- * Returns the nth private data pointer (starting from 0) matching, or an
- * ERR_PTR.
- * Returns the private data pointer, or an ERR_PTR.
- * The private data pointer should _only_ be dereferenced if the caller is the
- * owner of the data, or its content could vanish. This is mostly used to
- * confirm that a caller is the owner of a registered probe.
- */
-void *marker_get_private_data(const char *name, marker_probe_func *probe,
- int num)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct marker_entry *e;
- size_t name_len = strlen(name) + 1;
- u32 hash = jhash(name, name_len-1, 0);
- int i;
-
- head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
- hlist_for_each_entry(e, node, head, hlist) {
- if (!strcmp(name, e->name)) {
- if (!e->ptype) {
- if (num == 0 && e->single.func == probe)
- return e->single.probe_private;
- } else {
- struct marker_probe_closure *closure;
- int match = 0;
- closure = e->multi;
- for (i = 0; closure[i].func; i++) {
- if (closure[i].func != probe)
- continue;
- if (match++ == num)
- return closure[i].probe_private;
- }
- }
- break;
- }
- }
- return ERR_PTR(-ENOENT);
-}
-EXPORT_SYMBOL_GPL(marker_get_private_data);
-
-#ifdef CONFIG_MODULES
-
-int marker_module_notify(struct notifier_block *self,
- unsigned long val, void *data)
-{
- struct module *mod = data;
-
- switch (val) {
- case MODULE_STATE_COMING:
- marker_update_probe_range(mod->markers,
- mod->markers + mod->num_markers);
- break;
- case MODULE_STATE_GOING:
- marker_update_probe_range(mod->markers,
- mod->markers + mod->num_markers);
- break;
- }
- return 0;
-}
-
-struct notifier_block marker_module_nb = {
- .notifier_call = marker_module_notify,
- .priority = 0,
-};
-
-static int init_markers(void)
-{
- return register_module_notifier(&marker_module_nb);
-}
-__initcall(init_markers);
-
-#endif /* CONFIG_MODULES */
diff --git a/kernel/module.c b/kernel/module.c
index 05ce49ced8f..8b7d8805819 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -47,6 +47,7 @@
#include <linux/rculist.h>
#include <asm/uaccess.h>
#include <asm/cacheflush.h>
+#include <asm/mmu_context.h>
#include <linux/license.h>
#include <asm/sections.h>
#include <linux/tracepoint.h>
@@ -1535,6 +1536,10 @@ static void free_module(struct module *mod)
/* Finally, free the core (containing the module structure) */
module_free(mod, mod->module_core);
+
+#ifdef CONFIG_MPU
+ update_protections(current->mm);
+#endif
}
void *__symbol_get(const char *symbol)
@@ -1792,6 +1797,17 @@ static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
}
}
+static void free_modinfo(struct module *mod)
+{
+ struct module_attribute *attr;
+ int i;
+
+ for (i = 0; (attr = modinfo_attrs[i]); i++) {
+ if (attr->free)
+ attr->free(mod);
+ }
+}
+
#ifdef CONFIG_KALLSYMS
/* lookup symbol in given range of kernel_symbols */
@@ -1857,13 +1873,93 @@ static char elf_type(const Elf_Sym *sym,
return '?';
}
+static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
+ unsigned int shnum)
+{
+ const Elf_Shdr *sec;
+
+ if (src->st_shndx == SHN_UNDEF
+ || src->st_shndx >= shnum
+ || !src->st_name)
+ return false;
+
+ sec = sechdrs + src->st_shndx;
+ if (!(sec->sh_flags & SHF_ALLOC)
+#ifndef CONFIG_KALLSYMS_ALL
+ || !(sec->sh_flags & SHF_EXECINSTR)
+#endif
+ || (sec->sh_entsize & INIT_OFFSET_MASK))
+ return false;
+
+ return true;
+}
+
+static unsigned long layout_symtab(struct module *mod,
+ Elf_Shdr *sechdrs,
+ unsigned int symindex,
+ unsigned int strindex,
+ const Elf_Ehdr *hdr,
+ const char *secstrings,
+ unsigned long *pstroffs,
+ unsigned long *strmap)
+{
+ unsigned long symoffs;
+ Elf_Shdr *symsect = sechdrs + symindex;
+ Elf_Shdr *strsect = sechdrs + strindex;
+ const Elf_Sym *src;
+ const char *strtab;
+ unsigned int i, nsrc, ndst;
+
+ /* Put symbol section at end of init part of module. */
+ symsect->sh_flags |= SHF_ALLOC;
+ symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
+ symindex) | INIT_OFFSET_MASK;
+ DEBUGP("\t%s\n", secstrings + symsect->sh_name);
+
+ src = (void *)hdr + symsect->sh_offset;
+ nsrc = symsect->sh_size / sizeof(*src);
+ strtab = (void *)hdr + strsect->sh_offset;
+ for (ndst = i = 1; i < nsrc; ++i, ++src)
+ if (is_core_symbol(src, sechdrs, hdr->e_shnum)) {
+ unsigned int j = src->st_name;
+
+ while(!__test_and_set_bit(j, strmap) && strtab[j])
+ ++j;
+ ++ndst;
+ }
+
+ /* Append room for core symbols at end of core part. */
+ symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
+ mod->core_size = symoffs + ndst * sizeof(Elf_Sym);
+
+ /* Put string table section at end of init part of module. */
+ strsect->sh_flags |= SHF_ALLOC;
+ strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
+ strindex) | INIT_OFFSET_MASK;
+ DEBUGP("\t%s\n", secstrings + strsect->sh_name);
+
+ /* Append room for core symbols' strings at end of core part. */
+ *pstroffs = mod->core_size;
+ __set_bit(0, strmap);
+ mod->core_size += bitmap_weight(strmap, strsect->sh_size);
+
+ return symoffs;
+}
+
static void add_kallsyms(struct module *mod,
Elf_Shdr *sechdrs,
+ unsigned int shnum,
unsigned int symindex,
unsigned int strindex,
- const char *secstrings)
+ unsigned long symoffs,
+ unsigned long stroffs,
+ const char *secstrings,
+ unsigned long *strmap)
{
- unsigned int i;
+ unsigned int i, ndst;
+ const Elf_Sym *src;
+ Elf_Sym *dst;
+ char *s;
mod->symtab = (void *)sechdrs[symindex].sh_addr;
mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
@@ -1873,13 +1969,46 @@ static void add_kallsyms(struct module *mod,
for (i = 0; i < mod->num_symtab; i++)
mod->symtab[i].st_info
= elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
+
+ mod->core_symtab = dst = mod->module_core + symoffs;
+ src = mod->symtab;
+ *dst = *src;
+ for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
+ if (!is_core_symbol(src, sechdrs, shnum))
+ continue;
+ dst[ndst] = *src;
+ dst[ndst].st_name = bitmap_weight(strmap, dst[ndst].st_name);
+ ++ndst;
+ }
+ mod->core_num_syms = ndst;
+
+ mod->core_strtab = s = mod->module_core + stroffs;
+ for (*s = 0, i = 1; i < sechdrs[strindex].sh_size; ++i)
+ if (test_bit(i, strmap))
+ *++s = mod->strtab[i];
}
#else
+static inline unsigned long layout_symtab(struct module *mod,
+ Elf_Shdr *sechdrs,
+ unsigned int symindex,
+ unsigned int strindex,
+ const Elf_Ehdr *hdr,
+ const char *secstrings,
+ unsigned long *pstroffs,
+ unsigned long *strmap)
+{
+ return 0;
+}
+
static inline void add_kallsyms(struct module *mod,
Elf_Shdr *sechdrs,
+ unsigned int shnum,
unsigned int symindex,
unsigned int strindex,
- const char *secstrings)
+ unsigned long symoffs,
+ unsigned long stroffs,
+ const char *secstrings,
+ const unsigned long *strmap)
{
}
#endif /* CONFIG_KALLSYMS */
@@ -1954,6 +2083,8 @@ static noinline struct module *load_module(void __user *umod,
struct module *mod;
long err = 0;
void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
+ unsigned long symoffs, stroffs, *strmap;
+
mm_segment_t old_fs;
DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
@@ -2035,11 +2166,6 @@ static noinline struct module *load_module(void __user *umod,
/* Don't keep modinfo and version sections. */
sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
-#ifdef CONFIG_KALLSYMS
- /* Keep symbol and string tables for decoding later. */
- sechdrs[symindex].sh_flags |= SHF_ALLOC;
- sechdrs[strindex].sh_flags |= SHF_ALLOC;
-#endif
/* Check module struct version now, before we try to use module. */
if (!check_modstruct_version(sechdrs, versindex, mod)) {
@@ -2075,6 +2201,13 @@ static noinline struct module *load_module(void __user *umod,
goto free_hdr;
}
+ strmap = kzalloc(BITS_TO_LONGS(sechdrs[strindex].sh_size)
+ * sizeof(long), GFP_KERNEL);
+ if (!strmap) {
+ err = -ENOMEM;
+ goto free_mod;
+ }
+
if (find_module(mod->name)) {
err = -EEXIST;
goto free_mod;
@@ -2104,6 +2237,8 @@ static noinline struct module *load_module(void __user *umod,
this is done generically; there doesn't appear to be any
special cases for the architectures. */
layout_sections(mod, hdr, sechdrs, secstrings);
+ symoffs = layout_symtab(mod, sechdrs, symindex, strindex, hdr,
+ secstrings, &stroffs, strmap);
/* Do the allocs. */
ptr = module_alloc_update_bounds(mod->core_size);
@@ -2237,10 +2372,6 @@ static noinline struct module *load_module(void __user *umod,
sizeof(*mod->ctors), &mod->num_ctors);
#endif
-#ifdef CONFIG_MARKERS
- mod->markers = section_objs(hdr, sechdrs, secstrings, "__markers",
- sizeof(*mod->markers), &mod->num_markers);
-#endif
#ifdef CONFIG_TRACEPOINTS
mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
"__tracepoints",
@@ -2312,7 +2443,10 @@ static noinline struct module *load_module(void __user *umod,
percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
sechdrs[pcpuindex].sh_size);
- add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
+ add_kallsyms(mod, sechdrs, hdr->e_shnum, symindex, strindex,
+ symoffs, stroffs, secstrings, strmap);
+ kfree(strmap);
+ strmap = NULL;
if (!mod->taints) {
struct _ddebug *debug;
@@ -2384,13 +2518,14 @@ static noinline struct module *load_module(void __user *umod,
synchronize_sched();
module_arch_cleanup(mod);
cleanup:
+ free_modinfo(mod);
kobject_del(&mod->mkobj.kobj);
kobject_put(&mod->mkobj.kobj);
free_unload:
module_unload_free(mod);
#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
- free_init:
percpu_modfree(mod->refptr);
+ free_init:
#endif
module_free(mod, mod->module_init);
free_core:
@@ -2401,6 +2536,7 @@ static noinline struct module *load_module(void __user *umod,
percpu_modfree(percpu);
free_mod:
kfree(args);
+ kfree(strmap);
free_hdr:
vfree(hdr);
return ERR_PTR(err);
@@ -2490,6 +2626,11 @@ SYSCALL_DEFINE3(init_module, void __user *, umod,
/* Drop initial reference. */
module_put(mod);
trim_init_extable(mod);
+#ifdef CONFIG_KALLSYMS
+ mod->num_symtab = mod->core_num_syms;
+ mod->symtab = mod->core_symtab;
+ mod->strtab = mod->core_strtab;
+#endif
module_free(mod, mod->module_init);
mod->module_init = NULL;
mod->init_size = 0;
@@ -2951,27 +3092,12 @@ void module_layout(struct module *mod,
struct modversion_info *ver,
struct kernel_param *kp,
struct kernel_symbol *ks,
- struct marker *marker,
struct tracepoint *tp)
{
}
EXPORT_SYMBOL(module_layout);
#endif
-#ifdef CONFIG_MARKERS
-void module_update_markers(void)
-{
- struct module *mod;
-
- mutex_lock(&module_mutex);
- list_for_each_entry(mod, &modules, list)
- if (!mod->taints)
- marker_update_probe_range(mod->markers,
- mod->markers + mod->num_markers);
- mutex_unlock(&module_mutex);
-}
-#endif
-
#ifdef CONFIG_TRACEPOINTS
void module_update_tracepoints(void)
{
diff --git a/kernel/ns_cgroup.c b/kernel/ns_cgroup.c
index 5aa854f9e5a..2a5dfec8efe 100644
--- a/kernel/ns_cgroup.c
+++ b/kernel/ns_cgroup.c
@@ -42,8 +42,8 @@ int ns_cgroup_clone(struct task_struct *task, struct pid *pid)
* (hence either you are in the same cgroup as task, or in an
* ancestor cgroup thereof)
*/
-static int ns_can_attach(struct cgroup_subsys *ss,
- struct cgroup *new_cgroup, struct task_struct *task)
+static int ns_can_attach(struct cgroup_subsys *ss, struct cgroup *new_cgroup,
+ struct task_struct *task, bool threadgroup)
{
if (current != task) {
if (!capable(CAP_SYS_ADMIN))
@@ -56,6 +56,18 @@ static int ns_can_attach(struct cgroup_subsys *ss,
if (!cgroup_is_descendant(new_cgroup, task))
return -EPERM;
+ if (threadgroup) {
+ struct task_struct *c;
+ rcu_read_lock();
+ list_for_each_entry_rcu(c, &task->thread_group, thread_group) {
+ if (!cgroup_is_descendant(new_cgroup, c)) {
+ rcu_read_unlock();
+ return -EPERM;
+ }
+ }
+ rcu_read_unlock();
+ }
+
return 0;
}
diff --git a/kernel/panic.c b/kernel/panic.c
index 512ab73b0ca..bcdef26e333 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -177,7 +177,7 @@ static const struct tnt tnts[] = {
* 'W' - Taint on warning.
* 'C' - modules from drivers/staging are loaded.
*
- * The string is overwritten by the next call to print_taint().
+ * The string is overwritten by the next call to print_tainted().
*/
const char *print_tainted(void)
{
diff --git a/kernel/params.c b/kernel/params.c
index 7f6912ced2b..9da58eabdcb 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -23,6 +23,7 @@
#include <linux/device.h>
#include <linux/err.h>
#include <linux/slab.h>
+#include <linux/ctype.h>
#if 0
#define DEBUGP printk
@@ -87,7 +88,7 @@ static char *next_arg(char *args, char **param, char **val)
}
for (i = 0; args[i]; i++) {
- if (args[i] == ' ' && !in_quote)
+ if (isspace(args[i]) && !in_quote)
break;
if (equals == 0) {
if (args[i] == '=')
@@ -121,7 +122,7 @@ static char *next_arg(char *args, char **param, char **val)
next = args + i;
/* Chew up trailing spaces. */
- while (*next == ' ')
+ while (isspace(*next))
next++;
return next;
}
@@ -138,7 +139,7 @@ int parse_args(const char *name,
DEBUGP("Parsing ARGS: %s\n", args);
/* Chew leading spaces */
- while (*args == ' ')
+ while (isspace(*args))
args++;
while (*args) {
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
deleted file mode 100644
index 8cb94a52d1b..00000000000
--- a/kernel/perf_counter.c
+++ /dev/null
@@ -1,4963 +0,0 @@
-/*
- * Performance counter core code
- *
- * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
- * Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar
- * Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
- * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
- *
- * For licensing details see kernel-base/COPYING
- */
-
-#include <linux/fs.h>
-#include <linux/mm.h>
-#include <linux/cpu.h>
-#include <linux/smp.h>
-#include <linux/file.h>
-#include <linux/poll.h>
-#include <linux/sysfs.h>
-#include <linux/dcache.h>
-#include <linux/percpu.h>
-#include <linux/ptrace.h>
-#include <linux/vmstat.h>
-#include <linux/hardirq.h>
-#include <linux/rculist.h>
-#include <linux/uaccess.h>
-#include <linux/syscalls.h>
-#include <linux/anon_inodes.h>
-#include <linux/kernel_stat.h>
-#include <linux/perf_counter.h>
-
-#include <asm/irq_regs.h>
-
-/*
- * Each CPU has a list of per CPU counters:
- */
-DEFINE_PER_CPU(struct perf_cpu_context, perf_cpu_context);
-
-int perf_max_counters __read_mostly = 1;
-static int perf_reserved_percpu __read_mostly;
-static int perf_overcommit __read_mostly = 1;
-
-static atomic_t nr_counters __read_mostly;
-static atomic_t nr_mmap_counters __read_mostly;
-static atomic_t nr_comm_counters __read_mostly;
-static atomic_t nr_task_counters __read_mostly;
-
-/*
- * perf counter paranoia level:
- * -1 - not paranoid at all
- * 0 - disallow raw tracepoint access for unpriv
- * 1 - disallow cpu counters for unpriv
- * 2 - disallow kernel profiling for unpriv
- */
-int sysctl_perf_counter_paranoid __read_mostly = 1;
-
-static inline bool perf_paranoid_tracepoint_raw(void)
-{
- return sysctl_perf_counter_paranoid > -1;
-}
-
-static inline bool perf_paranoid_cpu(void)
-{
- return sysctl_perf_counter_paranoid > 0;
-}
-
-static inline bool perf_paranoid_kernel(void)
-{
- return sysctl_perf_counter_paranoid > 1;
-}
-
-int sysctl_perf_counter_mlock __read_mostly = 512; /* 'free' kb per user */
-
-/*
- * max perf counter sample rate
- */
-int sysctl_perf_counter_sample_rate __read_mostly = 100000;
-
-static atomic64_t perf_counter_id;
-
-/*
- * Lock for (sysadmin-configurable) counter reservations:
- */
-static DEFINE_SPINLOCK(perf_resource_lock);
-
-/*
- * Architecture provided APIs - weak aliases:
- */
-extern __weak const struct pmu *hw_perf_counter_init(struct perf_counter *counter)
-{
- return NULL;
-}
-
-void __weak hw_perf_disable(void) { barrier(); }
-void __weak hw_perf_enable(void) { barrier(); }
-
-void __weak hw_perf_counter_setup(int cpu) { barrier(); }
-void __weak hw_perf_counter_setup_online(int cpu) { barrier(); }
-
-int __weak
-hw_perf_group_sched_in(struct perf_counter *group_leader,
- struct perf_cpu_context *cpuctx,
- struct perf_counter_context *ctx, int cpu)
-{
- return 0;
-}
-
-void __weak perf_counter_print_debug(void) { }
-
-static DEFINE_PER_CPU(int, perf_disable_count);
-
-void __perf_disable(void)
-{
- __get_cpu_var(perf_disable_count)++;
-}
-
-bool __perf_enable(void)
-{
- return !--__get_cpu_var(perf_disable_count);
-}
-
-void perf_disable(void)
-{
- __perf_disable();
- hw_perf_disable();
-}
-
-void perf_enable(void)
-{
- if (__perf_enable())
- hw_perf_enable();
-}
-
-static void get_ctx(struct perf_counter_context *ctx)
-{
- WARN_ON(!atomic_inc_not_zero(&ctx->refcount));
-}
-
-static void free_ctx(struct rcu_head *head)
-{
- struct perf_counter_context *ctx;
-
- ctx = container_of(head, struct perf_counter_context, rcu_head);
- kfree(ctx);
-}
-
-static void put_ctx(struct perf_counter_context *ctx)
-{
- if (atomic_dec_and_test(&ctx->refcount)) {
- if (ctx->parent_ctx)
- put_ctx(ctx->parent_ctx);
- if (ctx->task)
- put_task_struct(ctx->task);
- call_rcu(&ctx->rcu_head, free_ctx);
- }
-}
-
-static void unclone_ctx(struct perf_counter_context *ctx)
-{
- if (ctx->parent_ctx) {
- put_ctx(ctx->parent_ctx);
- ctx->parent_ctx = NULL;
- }
-}
-
-/*
- * If we inherit counters we want to return the parent counter id
- * to userspace.
- */
-static u64 primary_counter_id(struct perf_counter *counter)
-{
- u64 id = counter->id;
-
- if (counter->parent)
- id = counter->parent->id;
-
- return id;
-}
-
-/*
- * Get the perf_counter_context for a task and lock it.
- * This has to cope with with the fact that until it is locked,
- * the context could get moved to another task.
- */
-static struct perf_counter_context *
-perf_lock_task_context(struct task_struct *task, unsigned long *flags)
-{
- struct perf_counter_context *ctx;
-
- rcu_read_lock();
- retry:
- ctx = rcu_dereference(task->perf_counter_ctxp);
- if (ctx) {
- /*
- * If this context is a clone of another, it might
- * get swapped for another underneath us by
- * perf_counter_task_sched_out, though the
- * rcu_read_lock() protects us from any context
- * getting freed. Lock the context and check if it
- * got swapped before we could get the lock, and retry
- * if so. If we locked the right context, then it
- * can't get swapped on us any more.
- */
- spin_lock_irqsave(&ctx->lock, *flags);
- if (ctx != rcu_dereference(task->perf_counter_ctxp)) {
- spin_unlock_irqrestore(&ctx->lock, *flags);
- goto retry;
- }
-
- if (!atomic_inc_not_zero(&ctx->refcount)) {
- spin_unlock_irqrestore(&ctx->lock, *flags);
- ctx = NULL;
- }
- }
- rcu_read_unlock();
- return ctx;
-}
-
-/*
- * Get the context for a task and increment its pin_count so it
- * can't get swapped to another task. This also increments its
- * reference count so that the context can't get freed.
- */
-static struct perf_counter_context *perf_pin_task_context(struct task_struct *task)
-{
- struct perf_counter_context *ctx;
- unsigned long flags;
-
- ctx = perf_lock_task_context(task, &flags);
- if (ctx) {
- ++ctx->pin_count;
- spin_unlock_irqrestore(&ctx->lock, flags);
- }
- return ctx;
-}
-
-static void perf_unpin_context(struct perf_counter_context *ctx)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&ctx->lock, flags);
- --ctx->pin_count;
- spin_unlock_irqrestore(&ctx->lock, flags);
- put_ctx(ctx);
-}
-
-/*
- * Add a counter from the lists for its context.
- * Must be called with ctx->mutex and ctx->lock held.
- */
-static void
-list_add_counter(struct perf_counter *counter, struct perf_counter_context *ctx)
-{
- struct perf_counter *group_leader = counter->group_leader;
-
- /*
- * Depending on whether it is a standalone or sibling counter,
- * add it straight to the context's counter list, or to the group
- * leader's sibling list:
- */
- if (group_leader == counter)
- list_add_tail(&counter->list_entry, &ctx->counter_list);
- else {
- list_add_tail(&counter->list_entry, &group_leader->sibling_list);
- group_leader->nr_siblings++;
- }
-
- list_add_rcu(&counter->event_entry, &ctx->event_list);
- ctx->nr_counters++;
- if (counter->attr.inherit_stat)
- ctx->nr_stat++;
-}
-
-/*
- * Remove a counter from the lists for its context.
- * Must be called with ctx->mutex and ctx->lock held.
- */
-static void
-list_del_counter(struct perf_counter *counter, struct perf_counter_context *ctx)
-{
- struct perf_counter *sibling, *tmp;
-
- if (list_empty(&counter->list_entry))
- return;
- ctx->nr_counters--;
- if (counter->attr.inherit_stat)
- ctx->nr_stat--;
-
- list_del_init(&counter->list_entry);
- list_del_rcu(&counter->event_entry);
-
- if (counter->group_leader != counter)
- counter->group_leader->nr_siblings--;
-
- /*
- * If this was a group counter with sibling counters then
- * upgrade the siblings to singleton counters by adding them
- * to the context list directly:
- */
- list_for_each_entry_safe(sibling, tmp,
- &counter->sibling_list, list_entry) {
-
- list_move_tail(&sibling->list_entry, &ctx->counter_list);
- sibling->group_leader = sibling;
- }
-}
-
-static void
-counter_sched_out(struct perf_counter *counter,
- struct perf_cpu_context *cpuctx,
- struct perf_counter_context *ctx)
-{
- if (counter->state != PERF_COUNTER_STATE_ACTIVE)
- return;
-
- counter->state = PERF_COUNTER_STATE_INACTIVE;
- if (counter->pending_disable) {
- counter->pending_disable = 0;
- counter->state = PERF_COUNTER_STATE_OFF;
- }
- counter->tstamp_stopped = ctx->time;
- counter->pmu->disable(counter);
- counter->oncpu = -1;
-
- if (!is_software_counter(counter))
- cpuctx->active_oncpu--;
- ctx->nr_active--;
- if (counter->attr.exclusive || !cpuctx->active_oncpu)
- cpuctx->exclusive = 0;
-}
-
-static void
-group_sched_out(struct perf_counter *group_counter,
- struct perf_cpu_context *cpuctx,
- struct perf_counter_context *ctx)
-{
- struct perf_counter *counter;
-
- if (group_counter->state != PERF_COUNTER_STATE_ACTIVE)
- return;
-
- counter_sched_out(group_counter, cpuctx, ctx);
-
- /*
- * Schedule out siblings (if any):
- */
- list_for_each_entry(counter, &group_counter->sibling_list, list_entry)
- counter_sched_out(counter, cpuctx, ctx);
-
- if (group_counter->attr.exclusive)
- cpuctx->exclusive = 0;
-}
-
-/*
- * Cross CPU call to remove a performance counter
- *
- * We disable the counter on the hardware level first. After that we
- * remove it from the context list.
- */
-static void __perf_counter_remove_from_context(void *info)
-{
- struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
- struct perf_counter *counter = info;
- struct perf_counter_context *ctx = counter->ctx;
-
- /*
- * If this is a task context, we need to check whether it is
- * the current task context of this cpu. If not it has been
- * scheduled out before the smp call arrived.
- */
- if (ctx->task && cpuctx->task_ctx != ctx)
- return;
-
- spin_lock(&ctx->lock);
- /*
- * Protect the list operation against NMI by disabling the
- * counters on a global level.
- */
- perf_disable();
-
- counter_sched_out(counter, cpuctx, ctx);
-
- list_del_counter(counter, ctx);
-
- if (!ctx->task) {
- /*
- * Allow more per task counters with respect to the
- * reservation:
- */
- cpuctx->max_pertask =
- min(perf_max_counters - ctx->nr_counters,
- perf_max_counters - perf_reserved_percpu);
- }
-
- perf_enable();
- spin_unlock(&ctx->lock);
-}
-
-
-/*
- * Remove the counter from a task's (or a CPU's) list of counters.
- *
- * Must be called with ctx->mutex held.
- *
- * CPU counters are removed with a smp call. For task counters we only
- * call when the task is on a CPU.
- *
- * If counter->ctx is a cloned context, callers must make sure that
- * every task struct that counter->ctx->task could possibly point to
- * remains valid. This is OK when called from perf_release since
- * that only calls us on the top-level context, which can't be a clone.
- * When called from perf_counter_exit_task, it's OK because the
- * context has been detached from its task.
- */
-static void perf_counter_remove_from_context(struct perf_counter *counter)
-{
- struct perf_counter_context *ctx = counter->ctx;
- struct task_struct *task = ctx->task;
-
- if (!task) {
- /*
- * Per cpu counters are removed via an smp call and
- * the removal is always sucessful.
- */
- smp_call_function_single(counter->cpu,
- __perf_counter_remove_from_context,
- counter, 1);
- return;
- }
-
-retry:
- task_oncpu_function_call(task, __perf_counter_remove_from_context,
- counter);
-
- spin_lock_irq(&ctx->lock);
- /*
- * If the context is active we need to retry the smp call.
- */
- if (ctx->nr_active && !list_empty(&counter->list_entry)) {
- spin_unlock_irq(&ctx->lock);
- goto retry;
- }
-
- /*
- * The lock prevents that this context is scheduled in so we
- * can remove the counter safely, if the call above did not
- * succeed.
- */
- if (!list_empty(&counter->list_entry)) {
- list_del_counter(counter, ctx);
- }
- spin_unlock_irq(&ctx->lock);
-}
-
-static inline u64 perf_clock(void)
-{
- return cpu_clock(smp_processor_id());
-}
-
-/*
- * Update the record of the current time in a context.
- */
-static void update_context_time(struct perf_counter_context *ctx)
-{
- u64 now = perf_clock();
-
- ctx->time += now - ctx->timestamp;
- ctx->timestamp = now;
-}
-
-/*
- * Update the total_time_enabled and total_time_running fields for a counter.
- */
-static void update_counter_times(struct perf_counter *counter)
-{
- struct perf_counter_context *ctx = counter->ctx;
- u64 run_end;
-
- if (counter->state < PERF_COUNTER_STATE_INACTIVE ||
- counter->group_leader->state < PERF_COUNTER_STATE_INACTIVE)
- return;
-
- counter->total_time_enabled = ctx->time - counter->tstamp_enabled;
-
- if (counter->state == PERF_COUNTER_STATE_INACTIVE)
- run_end = counter->tstamp_stopped;
- else
- run_end = ctx->time;
-
- counter->total_time_running = run_end - counter->tstamp_running;
-}
-
-/*
- * Update total_time_enabled and total_time_running for all counters in a group.
- */
-static void update_group_times(struct perf_counter *leader)
-{
- struct perf_counter *counter;
-
- update_counter_times(leader);
- list_for_each_entry(counter, &leader->sibling_list, list_entry)
- update_counter_times(counter);
-}
-
-/*
- * Cross CPU call to disable a performance counter
- */
-static void __perf_counter_disable(void *info)
-{
- struct perf_counter *counter = info;
- struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
- struct perf_counter_context *ctx = counter->ctx;
-
- /*
- * If this is a per-task counter, need to check whether this
- * counter's task is the current task on this cpu.
- */
- if (ctx->task && cpuctx->task_ctx != ctx)
- return;
-
- spin_lock(&ctx->lock);
-
- /*
- * If the counter is on, turn it off.
- * If it is in error state, leave it in error state.
- */
- if (counter->state >= PERF_COUNTER_STATE_INACTIVE) {
- update_context_time(ctx);
- update_group_times(counter);
- if (counter == counter->group_leader)
- group_sched_out(counter, cpuctx, ctx);
- else
- counter_sched_out(counter, cpuctx, ctx);
- counter->state = PERF_COUNTER_STATE_OFF;
- }
-
- spin_unlock(&ctx->lock);
-}
-
-/*
- * Disable a counter.
- *
- * If counter->ctx is a cloned context, callers must make sure that
- * every task struct that counter->ctx->task could possibly point to
- * remains valid. This condition is satisifed when called through
- * perf_counter_for_each_child or perf_counter_for_each because they
- * hold the top-level counter's child_mutex, so any descendant that
- * goes to exit will block in sync_child_counter.
- * When called from perf_pending_counter it's OK because counter->ctx
- * is the current context on this CPU and preemption is disabled,
- * hence we can't get into perf_counter_task_sched_out for this context.
- */
-static void perf_counter_disable(struct perf_counter *counter)
-{
- struct perf_counter_context *ctx = counter->ctx;
- struct task_struct *task = ctx->task;
-
- if (!task) {
- /*
- * Disable the counter on the cpu that it's on
- */
- smp_call_function_single(counter->cpu, __perf_counter_disable,
- counter, 1);
- return;
- }
-
- retry:
- task_oncpu_function_call(task, __perf_counter_disable, counter);
-
- spin_lock_irq(&ctx->lock);
- /*
- * If the counter is still active, we need to retry the cross-call.
- */
- if (counter->state == PERF_COUNTER_STATE_ACTIVE) {
- spin_unlock_irq(&ctx->lock);
- goto retry;
- }
-
- /*
- * Since we have the lock this context can't be scheduled
- * in, so we can change the state safely.
- */
- if (counter->state == PERF_COUNTER_STATE_INACTIVE) {
- update_group_times(counter);
- counter->state = PERF_COUNTER_STATE_OFF;
- }
-
- spin_unlock_irq(&ctx->lock);
-}
-
-static int
-counter_sched_in(struct perf_counter *counter,
- struct perf_cpu_context *cpuctx,
- struct perf_counter_context *ctx,
- int cpu)
-{
- if (counter->state <= PERF_COUNTER_STATE_OFF)
- return 0;
-
- counter->state = PERF_COUNTER_STATE_ACTIVE;
- counter->oncpu = cpu; /* TODO: put 'cpu' into cpuctx->cpu */
- /*
- * The new state must be visible before we turn it on in the hardware:
- */
- smp_wmb();
-
- if (counter->pmu->enable(counter)) {
- counter->state = PERF_COUNTER_STATE_INACTIVE;
- counter->oncpu = -1;
- return -EAGAIN;
- }
-
- counter->tstamp_running += ctx->time - counter->tstamp_stopped;
-
- if (!is_software_counter(counter))
- cpuctx->active_oncpu++;
- ctx->nr_active++;
-
- if (counter->attr.exclusive)
- cpuctx->exclusive = 1;
-
- return 0;
-}
-
-static int
-group_sched_in(struct perf_counter *group_counter,
- struct perf_cpu_context *cpuctx,
- struct perf_counter_context *ctx,
- int cpu)
-{
- struct perf_counter *counter, *partial_group;
- int ret;
-
- if (group_counter->state == PERF_COUNTER_STATE_OFF)
- return 0;
-
- ret = hw_perf_group_sched_in(group_counter, cpuctx, ctx, cpu);
- if (ret)
- return ret < 0 ? ret : 0;
-
- if (counter_sched_in(group_counter, cpuctx, ctx, cpu))
- return -EAGAIN;
-
- /*
- * Schedule in siblings as one group (if any):
- */
- list_for_each_entry(counter, &group_counter->sibling_list, list_entry) {
- if (counter_sched_in(counter, cpuctx, ctx, cpu)) {
- partial_group = counter;
- goto group_error;
- }
- }
-
- return 0;
-
-group_error:
- /*
- * Groups can be scheduled in as one unit only, so undo any
- * partial group before returning:
- */
- list_for_each_entry(counter, &group_counter->sibling_list, list_entry) {
- if (counter == partial_group)
- break;
- counter_sched_out(counter, cpuctx, ctx);
- }
- counter_sched_out(group_counter, cpuctx, ctx);
-
- return -EAGAIN;
-}
-
-/*
- * Return 1 for a group consisting entirely of software counters,
- * 0 if the group contains any hardware counters.
- */
-static int is_software_only_group(struct perf_counter *leader)
-{
- struct perf_counter *counter;
-
- if (!is_software_counter(leader))
- return 0;
-
- list_for_each_entry(counter, &leader->sibling_list, list_entry)
- if (!is_software_counter(counter))
- return 0;
-
- return 1;
-}
-
-/*
- * Work out whether we can put this counter group on the CPU now.
- */
-static int group_can_go_on(struct perf_counter *counter,
- struct perf_cpu_context *cpuctx,
- int can_add_hw)
-{
- /*
- * Groups consisting entirely of software counters can always go on.
- */
- if (is_software_only_group(counter))
- return 1;
- /*
- * If an exclusive group is already on, no other hardware
- * counters can go on.
- */
- if (cpuctx->exclusive)
- return 0;
- /*
- * If this group is exclusive and there are already
- * counters on the CPU, it can't go on.
- */
- if (counter->attr.exclusive && cpuctx->active_oncpu)
- return 0;
- /*
- * Otherwise, try to add it if all previous groups were able
- * to go on.
- */
- return can_add_hw;
-}
-
-static void add_counter_to_ctx(struct perf_counter *counter,
- struct perf_counter_context *ctx)
-{
- list_add_counter(counter, ctx);
- counter->tstamp_enabled = ctx->time;
- counter->tstamp_running = ctx->time;
- counter->tstamp_stopped = ctx->time;
-}
-
-/*
- * Cross CPU call to install and enable a performance counter
- *
- * Must be called with ctx->mutex held
- */
-static void __perf_install_in_context(void *info)
-{
- struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
- struct perf_counter *counter = info;
- struct perf_counter_context *ctx = counter->ctx;
- struct perf_counter *leader = counter->group_leader;
- int cpu = smp_processor_id();
- int err;
-
- /*
- * If this is a task context, we need to check whether it is
- * the current task context of this cpu. If not it has been
- * scheduled out before the smp call arrived.
- * Or possibly this is the right context but it isn't
- * on this cpu because it had no counters.
- */
- if (ctx->task && cpuctx->task_ctx != ctx) {
- if (cpuctx->task_ctx || ctx->task != current)
- return;
- cpuctx->task_ctx = ctx;
- }
-
- spin_lock(&ctx->lock);
- ctx->is_active = 1;
- update_context_time(ctx);
-
- /*
- * Protect the list operation against NMI by disabling the
- * counters on a global level. NOP for non NMI based counters.
- */
- perf_disable();
-
- add_counter_to_ctx(counter, ctx);
-
- /*
- * Don't put the counter on if it is disabled or if
- * it is in a group and the group isn't on.
- */
- if (counter->state != PERF_COUNTER_STATE_INACTIVE ||
- (leader != counter && leader->state != PERF_COUNTER_STATE_ACTIVE))
- goto unlock;
-
- /*
- * An exclusive counter can't go on if there are already active
- * hardware counters, and no hardware counter can go on if there
- * is already an exclusive counter on.
- */
- if (!group_can_go_on(counter, cpuctx, 1))
- err = -EEXIST;
- else
- err = counter_sched_in(counter, cpuctx, ctx, cpu);
-
- if (err) {
- /*
- * This counter couldn't go on. If it is in a group
- * then we have to pull the whole group off.
- * If the counter group is pinned then put it in error state.
- */
- if (leader != counter)
- group_sched_out(leader, cpuctx, ctx);
- if (leader->attr.pinned) {
- update_group_times(leader);
- leader->state = PERF_COUNTER_STATE_ERROR;
- }
- }
-
- if (!err && !ctx->task && cpuctx->max_pertask)
- cpuctx->max_pertask--;
-
- unlock:
- perf_enable();
-
- spin_unlock(&ctx->lock);
-}
-
-/*
- * Attach a performance counter to a context
- *
- * First we add the counter to the list with the hardware enable bit
- * in counter->hw_config cleared.
- *
- * If the counter is attached to a task which is on a CPU we use a smp
- * call to enable it in the task context. The task might have been
- * scheduled away, but we check this in the smp call again.
- *
- * Must be called with ctx->mutex held.
- */
-static void
-perf_install_in_context(struct perf_counter_context *ctx,
- struct perf_counter *counter,
- int cpu)
-{
- struct task_struct *task = ctx->task;
-
- if (!task) {
- /*
- * Per cpu counters are installed via an smp call and
- * the install is always sucessful.
- */
- smp_call_function_single(cpu, __perf_install_in_context,
- counter, 1);
- return;
- }
-
-retry:
- task_oncpu_function_call(task, __perf_install_in_context,
- counter);
-
- spin_lock_irq(&ctx->lock);
- /*
- * we need to retry the smp call.
- */
- if (ctx->is_active && list_empty(&counter->list_entry)) {
- spin_unlock_irq(&ctx->lock);
- goto retry;
- }
-
- /*
- * The lock prevents that this context is scheduled in so we
- * can add the counter safely, if it the call above did not
- * succeed.
- */
- if (list_empty(&counter->list_entry))
- add_counter_to_ctx(counter, ctx);
- spin_unlock_irq(&ctx->lock);
-}
-
-/*
- * Put a counter into inactive state and update time fields.
- * Enabling the leader of a group effectively enables all
- * the group members that aren't explicitly disabled, so we
- * have to update their ->tstamp_enabled also.
- * Note: this works for group members as well as group leaders
- * since the non-leader members' sibling_lists will be empty.
- */
-static void __perf_counter_mark_enabled(struct perf_counter *counter,
- struct perf_counter_context *ctx)
-{
- struct perf_counter *sub;
-
- counter->state = PERF_COUNTER_STATE_INACTIVE;
- counter->tstamp_enabled = ctx->time - counter->total_time_enabled;
- list_for_each_entry(sub, &counter->sibling_list, list_entry)
- if (sub->state >= PERF_COUNTER_STATE_INACTIVE)
- sub->tstamp_enabled =
- ctx->time - sub->total_time_enabled;
-}
-
-/*
- * Cross CPU call to enable a performance counter
- */
-static void __perf_counter_enable(void *info)
-{
- struct perf_counter *counter = info;
- struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
- struct perf_counter_context *ctx = counter->ctx;
- struct perf_counter *leader = counter->group_leader;
- int err;
-
- /*
- * If this is a per-task counter, need to check whether this
- * counter's task is the current task on this cpu.
- */
- if (ctx->task && cpuctx->task_ctx != ctx) {
- if (cpuctx->task_ctx || ctx->task != current)
- return;
- cpuctx->task_ctx = ctx;
- }
-
- spin_lock(&ctx->lock);
- ctx->is_active = 1;
- update_context_time(ctx);
-
- if (counter->state >= PERF_COUNTER_STATE_INACTIVE)
- goto unlock;
- __perf_counter_mark_enabled(counter, ctx);
-
- /*
- * If the counter is in a group and isn't the group leader,
- * then don't put it on unless the group is on.
- */
- if (leader != counter && leader->state != PERF_COUNTER_STATE_ACTIVE)
- goto unlock;
-
- if (!group_can_go_on(counter, cpuctx, 1)) {
- err = -EEXIST;
- } else {
- perf_disable();
- if (counter == leader)
- err = group_sched_in(counter, cpuctx, ctx,
- smp_processor_id());
- else
- err = counter_sched_in(counter, cpuctx, ctx,
- smp_processor_id());
- perf_enable();
- }
-
- if (err) {
- /*
- * If this counter can't go on and it's part of a
- * group, then the whole group has to come off.
- */
- if (leader != counter)
- group_sched_out(leader, cpuctx, ctx);
- if (leader->attr.pinned) {
- update_group_times(leader);
- leader->state = PERF_COUNTER_STATE_ERROR;
- }
- }
-
- unlock:
- spin_unlock(&ctx->lock);
-}
-
-/*
- * Enable a counter.
- *
- * If counter->ctx is a cloned context, callers must make sure that
- * every task struct that counter->ctx->task could possibly point to
- * remains valid. This condition is satisfied when called through
- * perf_counter_for_each_child or perf_counter_for_each as described
- * for perf_counter_disable.
- */
-static void perf_counter_enable(struct perf_counter *counter)
-{
- struct perf_counter_context *ctx = counter->ctx;
- struct task_struct *task = ctx->task;
-
- if (!task) {
- /*
- * Enable the counter on the cpu that it's on
- */
- smp_call_function_single(counter->cpu, __perf_counter_enable,
- counter, 1);
- return;
- }
-
- spin_lock_irq(&ctx->lock);
- if (counter->state >= PERF_COUNTER_STATE_INACTIVE)
- goto out;
-
- /*
- * If the counter is in error state, clear that first.
- * That way, if we see the counter in error state below, we
- * know that it has gone back into error state, as distinct
- * from the task having been scheduled away before the
- * cross-call arrived.
- */
- if (counter->state == PERF_COUNTER_STATE_ERROR)
- counter->state = PERF_COUNTER_STATE_OFF;
-
- retry:
- spin_unlock_irq(&ctx->lock);
- task_oncpu_function_call(task, __perf_counter_enable, counter);
-
- spin_lock_irq(&ctx->lock);
-
- /*
- * If the context is active and the counter is still off,
- * we need to retry the cross-call.
- */
- if (ctx->is_active && counter->state == PERF_COUNTER_STATE_OFF)
- goto retry;
-
- /*
- * Since we have the lock this context can't be scheduled
- * in, so we can change the state safely.
- */
- if (counter->state == PERF_COUNTER_STATE_OFF)
- __perf_counter_mark_enabled(counter, ctx);
-
- out:
- spin_unlock_irq(&ctx->lock);
-}
-
-static int perf_counter_refresh(struct perf_counter *counter, int refresh)
-{
- /*
- * not supported on inherited counters
- */
- if (counter->attr.inherit)
- return -EINVAL;
-
- atomic_add(refresh, &counter->event_limit);
- perf_counter_enable(counter);
-
- return 0;
-}
-
-void __perf_counter_sched_out(struct perf_counter_context *ctx,
- struct perf_cpu_context *cpuctx)
-{
- struct perf_counter *counter;
-
- spin_lock(&ctx->lock);
- ctx->is_active = 0;
- if (likely(!ctx->nr_counters))
- goto out;
- update_context_time(ctx);
-
- perf_disable();
- if (ctx->nr_active) {
- list_for_each_entry(counter, &ctx->counter_list, list_entry) {
- if (counter != counter->group_leader)
- counter_sched_out(counter, cpuctx, ctx);
- else
- group_sched_out(counter, cpuctx, ctx);
- }
- }
- perf_enable();
- out:
- spin_unlock(&ctx->lock);
-}
-
-/*
- * Test whether two contexts are equivalent, i.e. whether they
- * have both been cloned from the same version of the same context
- * and they both have the same number of enabled counters.
- * If the number of enabled counters is the same, then the set
- * of enabled counters should be the same, because these are both
- * inherited contexts, therefore we can't access individual counters
- * in them directly with an fd; we can only enable/disable all
- * counters via prctl, or enable/disable all counters in a family
- * via ioctl, which will have the same effect on both contexts.
- */
-static int context_equiv(struct perf_counter_context *ctx1,
- struct perf_counter_context *ctx2)
-{
- return ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx
- && ctx1->parent_gen == ctx2->parent_gen
- && !ctx1->pin_count && !ctx2->pin_count;
-}
-
-static void __perf_counter_read(void *counter);
-
-static void __perf_counter_sync_stat(struct perf_counter *counter,
- struct perf_counter *next_counter)
-{
- u64 value;
-
- if (!counter->attr.inherit_stat)
- return;
-
- /*
- * Update the counter value, we cannot use perf_counter_read()
- * because we're in the middle of a context switch and have IRQs
- * disabled, which upsets smp_call_function_single(), however
- * we know the counter must be on the current CPU, therefore we
- * don't need to use it.
- */
- switch (counter->state) {
- case PERF_COUNTER_STATE_ACTIVE:
- __perf_counter_read(counter);
- break;
-
- case PERF_COUNTER_STATE_INACTIVE:
- update_counter_times(counter);
- break;
-
- default:
- break;
- }
-
- /*
- * In order to keep per-task stats reliable we need to flip the counter
- * values when we flip the contexts.
- */
- value = atomic64_read(&next_counter->count);
- value = atomic64_xchg(&counter->count, value);
- atomic64_set(&next_counter->count, value);
-
- swap(counter->total_time_enabled, next_counter->total_time_enabled);
- swap(counter->total_time_running, next_counter->total_time_running);
-
- /*
- * Since we swizzled the values, update the user visible data too.
- */
- perf_counter_update_userpage(counter);
- perf_counter_update_userpage(next_counter);
-}
-
-#define list_next_entry(pos, member) \
- list_entry(pos->member.next, typeof(*pos), member)
-
-static void perf_counter_sync_stat(struct perf_counter_context *ctx,
- struct perf_counter_context *next_ctx)
-{
- struct perf_counter *counter, *next_counter;
-
- if (!ctx->nr_stat)
- return;
-
- counter = list_first_entry(&ctx->event_list,
- struct perf_counter, event_entry);
-
- next_counter = list_first_entry(&next_ctx->event_list,
- struct perf_counter, event_entry);
-
- while (&counter->event_entry != &ctx->event_list &&
- &next_counter->event_entry != &next_ctx->event_list) {
-
- __perf_counter_sync_stat(counter, next_counter);
-
- counter = list_next_entry(counter, event_entry);
- next_counter = list_next_entry(next_counter, event_entry);
- }
-}
-
-/*
- * Called from scheduler to remove the counters of the current task,
- * with interrupts disabled.
- *
- * We stop each counter and update the counter value in counter->count.
- *
- * This does not protect us against NMI, but disable()
- * sets the disabled bit in the control field of counter _before_
- * accessing the counter control register. If a NMI hits, then it will
- * not restart the counter.
- */
-void perf_counter_task_sched_out(struct task_struct *task,
- struct task_struct *next, int cpu)
-{
- struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
- struct perf_counter_context *ctx = task->perf_counter_ctxp;
- struct perf_counter_context *next_ctx;
- struct perf_counter_context *parent;
- struct pt_regs *regs;
- int do_switch = 1;
-
- regs = task_pt_regs(task);
- perf_swcounter_event(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 1, regs, 0);
-
- if (likely(!ctx || !cpuctx->task_ctx))
- return;
-
- update_context_time(ctx);
-
- rcu_read_lock();
- parent = rcu_dereference(ctx->parent_ctx);
- next_ctx = next->perf_counter_ctxp;
- if (parent && next_ctx &&
- rcu_dereference(next_ctx->parent_ctx) == parent) {
- /*
- * Looks like the two contexts are clones, so we might be
- * able to optimize the context switch. We lock both
- * contexts and check that they are clones under the
- * lock (including re-checking that neither has been
- * uncloned in the meantime). It doesn't matter which
- * order we take the locks because no other cpu could
- * be trying to lock both of these tasks.
- */
- spin_lock(&ctx->lock);
- spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING);
- if (context_equiv(ctx, next_ctx)) {
- /*
- * XXX do we need a memory barrier of sorts
- * wrt to rcu_dereference() of perf_counter_ctxp
- */
- task->perf_counter_ctxp = next_ctx;
- next->perf_counter_ctxp = ctx;
- ctx->task = next;
- next_ctx->task = task;
- do_switch = 0;
-
- perf_counter_sync_stat(ctx, next_ctx);
- }
- spin_unlock(&next_ctx->lock);
- spin_unlock(&ctx->lock);
- }
- rcu_read_unlock();
-
- if (do_switch) {
- __perf_counter_sched_out(ctx, cpuctx);
- cpuctx->task_ctx = NULL;
- }
-}
-
-/*
- * Called with IRQs disabled
- */
-static void __perf_counter_task_sched_out(struct perf_counter_context *ctx)
-{
- struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
-
- if (!cpuctx->task_ctx)
- return;
-
- if (WARN_ON_ONCE(ctx != cpuctx->task_ctx))
- return;
-
- __perf_counter_sched_out(ctx, cpuctx);
- cpuctx->task_ctx = NULL;
-}
-
-/*
- * Called with IRQs disabled
- */
-static void perf_counter_cpu_sched_out(struct perf_cpu_context *cpuctx)
-{
- __perf_counter_sched_out(&cpuctx->ctx, cpuctx);
-}
-
-static void
-__perf_counter_sched_in(struct perf_counter_context *ctx,
- struct perf_cpu_context *cpuctx, int cpu)
-{
- struct perf_counter *counter;
- int can_add_hw = 1;
-
- spin_lock(&ctx->lock);
- ctx->is_active = 1;
- if (likely(!ctx->nr_counters))
- goto out;
-
- ctx->timestamp = perf_clock();
-
- perf_disable();
-
- /*
- * First go through the list and put on any pinned groups
- * in order to give them the best chance of going on.
- */
- list_for_each_entry(counter, &ctx->counter_list, list_entry) {
- if (counter->state <= PERF_COUNTER_STATE_OFF ||
- !counter->attr.pinned)
- continue;
- if (counter->cpu != -1 && counter->cpu != cpu)
- continue;
-
- if (counter != counter->group_leader)
- counter_sched_in(counter, cpuctx, ctx, cpu);
- else {
- if (group_can_go_on(counter, cpuctx, 1))
- group_sched_in(counter, cpuctx, ctx, cpu);
- }
-
- /*
- * If this pinned group hasn't been scheduled,
- * put it in error state.
- */
- if (counter->state == PERF_COUNTER_STATE_INACTIVE) {
- update_group_times(counter);
- counter->state = PERF_COUNTER_STATE_ERROR;
- }
- }
-
- list_for_each_entry(counter, &ctx->counter_list, list_entry) {
- /*
- * Ignore counters in OFF or ERROR state, and
- * ignore pinned counters since we did them already.
- */
- if (counter->state <= PERF_COUNTER_STATE_OFF ||
- counter->attr.pinned)
- continue;
-
- /*
- * Listen to the 'cpu' scheduling filter constraint
- * of counters:
- */
- if (counter->cpu != -1 && counter->cpu != cpu)
- continue;
-
- if (counter != counter->group_leader) {
- if (counter_sched_in(counter, cpuctx, ctx, cpu))
- can_add_hw = 0;
- } else {
- if (group_can_go_on(counter, cpuctx, can_add_hw)) {
- if (group_sched_in(counter, cpuctx, ctx, cpu))
- can_add_hw = 0;
- }
- }
- }
- perf_enable();
- out:
- spin_unlock(&ctx->lock);
-}
-
-/*
- * Called from scheduler to add the counters of the current task
- * with interrupts disabled.
- *
- * We restore the counter value and then enable it.
- *
- * This does not protect us against NMI, but enable()
- * sets the enabled bit in the control field of counter _before_
- * accessing the counter control register. If a NMI hits, then it will
- * keep the counter running.
- */
-void perf_counter_task_sched_in(struct task_struct *task, int cpu)
-{
- struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
- struct perf_counter_context *ctx = task->perf_counter_ctxp;
-
- if (likely(!ctx))
- return;
- if (cpuctx->task_ctx == ctx)
- return;
- __perf_counter_sched_in(ctx, cpuctx, cpu);
- cpuctx->task_ctx = ctx;
-}
-
-static void perf_counter_cpu_sched_in(struct perf_cpu_context *cpuctx, int cpu)
-{
- struct perf_counter_context *ctx = &cpuctx->ctx;
-
- __perf_counter_sched_in(ctx, cpuctx, cpu);
-}
-
-#define MAX_INTERRUPTS (~0ULL)
-
-static void perf_log_throttle(struct perf_counter *counter, int enable);
-
-static void perf_adjust_period(struct perf_counter *counter, u64 events)
-{
- struct hw_perf_counter *hwc = &counter->hw;
- u64 period, sample_period;
- s64 delta;
-
- events *= hwc->sample_period;
- period = div64_u64(events, counter->attr.sample_freq);
-
- delta = (s64)(period - hwc->sample_period);
- delta = (delta + 7) / 8; /* low pass filter */
-
- sample_period = hwc->sample_period + delta;
-
- if (!sample_period)
- sample_period = 1;
-
- hwc->sample_period = sample_period;
-}
-
-static void perf_ctx_adjust_freq(struct perf_counter_context *ctx)
-{
- struct perf_counter *counter;
- struct hw_perf_counter *hwc;
- u64 interrupts, freq;
-
- spin_lock(&ctx->lock);
- list_for_each_entry(counter, &ctx->counter_list, list_entry) {
- if (counter->state != PERF_COUNTER_STATE_ACTIVE)
- continue;
-
- hwc = &counter->hw;
-
- interrupts = hwc->interrupts;
- hwc->interrupts = 0;
-
- /*
- * unthrottle counters on the tick
- */
- if (interrupts == MAX_INTERRUPTS) {
- perf_log_throttle(counter, 1);
- counter->pmu->unthrottle(counter);
- interrupts = 2*sysctl_perf_counter_sample_rate/HZ;
- }
-
- if (!counter->attr.freq || !counter->attr.sample_freq)
- continue;
-
- /*
- * if the specified freq < HZ then we need to skip ticks
- */
- if (counter->attr.sample_freq < HZ) {
- freq = counter->attr.sample_freq;
-
- hwc->freq_count += freq;
- hwc->freq_interrupts += interrupts;
-
- if (hwc->freq_count < HZ)
- continue;
-
- interrupts = hwc->freq_interrupts;
- hwc->freq_interrupts = 0;
- hwc->freq_count -= HZ;
- } else
- freq = HZ;
-
- perf_adjust_period(counter, freq * interrupts);
-
- /*
- * In order to avoid being stalled by an (accidental) huge
- * sample period, force reset the sample period if we didn't
- * get any events in this freq period.
- */
- if (!interrupts) {
- perf_disable();
- counter->pmu->disable(counter);
- atomic64_set(&hwc->period_left, 0);
- counter->pmu->enable(counter);
- perf_enable();
- }
- }
- spin_unlock(&ctx->lock);
-}
-
-/*
- * Round-robin a context's counters:
- */
-static void rotate_ctx(struct perf_counter_context *ctx)
-{
- struct perf_counter *counter;
-
- if (!ctx->nr_counters)
- return;
-
- spin_lock(&ctx->lock);
- /*
- * Rotate the first entry last (works just fine for group counters too):
- */
- perf_disable();
- list_for_each_entry(counter, &ctx->counter_list, list_entry) {
- list_move_tail(&counter->list_entry, &ctx->counter_list);
- break;
- }
- perf_enable();
-
- spin_unlock(&ctx->lock);
-}
-
-void perf_counter_task_tick(struct task_struct *curr, int cpu)
-{
- struct perf_cpu_context *cpuctx;
- struct perf_counter_context *ctx;
-
- if (!atomic_read(&nr_counters))
- return;
-
- cpuctx = &per_cpu(perf_cpu_context, cpu);
- ctx = curr->perf_counter_ctxp;
-
- perf_ctx_adjust_freq(&cpuctx->ctx);
- if (ctx)
- perf_ctx_adjust_freq(ctx);
-
- perf_counter_cpu_sched_out(cpuctx);
- if (ctx)
- __perf_counter_task_sched_out(ctx);
-
- rotate_ctx(&cpuctx->ctx);
- if (ctx)
- rotate_ctx(ctx);
-
- perf_counter_cpu_sched_in(cpuctx, cpu);
- if (ctx)
- perf_counter_task_sched_in(curr, cpu);
-}
-
-/*
- * Enable all of a task's counters that have been marked enable-on-exec.
- * This expects task == current.
- */
-static void perf_counter_enable_on_exec(struct task_struct *task)
-{
- struct perf_counter_context *ctx;
- struct perf_counter *counter;
- unsigned long flags;
- int enabled = 0;
-
- local_irq_save(flags);
- ctx = task->perf_counter_ctxp;
- if (!ctx || !ctx->nr_counters)
- goto out;
-
- __perf_counter_task_sched_out(ctx);
-
- spin_lock(&ctx->lock);
-
- list_for_each_entry(counter, &ctx->counter_list, list_entry) {
- if (!counter->attr.enable_on_exec)
- continue;
- counter->attr.enable_on_exec = 0;
- if (counter->state >= PERF_COUNTER_STATE_INACTIVE)
- continue;
- __perf_counter_mark_enabled(counter, ctx);
- enabled = 1;
- }
-
- /*
- * Unclone this context if we enabled any counter.
- */
- if (enabled)
- unclone_ctx(ctx);
-
- spin_unlock(&ctx->lock);
-
- perf_counter_task_sched_in(task, smp_processor_id());
- out:
- local_irq_restore(flags);
-}
-
-/*
- * Cross CPU call to read the hardware counter
- */
-static void __perf_counter_read(void *info)
-{
- struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
- struct perf_counter *counter = info;
- struct perf_counter_context *ctx = counter->ctx;
- unsigned long flags;
-
- /*
- * If this is a task context, we need to check whether it is
- * the current task context of this cpu. If not it has been
- * scheduled out before the smp call arrived. In that case
- * counter->count would have been updated to a recent sample
- * when the counter was scheduled out.
- */
- if (ctx->task && cpuctx->task_ctx != ctx)
- return;
-
- local_irq_save(flags);
- if (ctx->is_active)
- update_context_time(ctx);
- counter->pmu->read(counter);
- update_counter_times(counter);
- local_irq_restore(flags);
-}
-
-static u64 perf_counter_read(struct perf_counter *counter)
-{
- /*
- * If counter is enabled and currently active on a CPU, update the
- * value in the counter structure:
- */
- if (counter->state == PERF_COUNTER_STATE_ACTIVE) {
- smp_call_function_single(counter->oncpu,
- __perf_counter_read, counter, 1);
- } else if (counter->state == PERF_COUNTER_STATE_INACTIVE) {
- update_counter_times(counter);
- }
-
- return atomic64_read(&counter->count);
-}
-
-/*
- * Initialize the perf_counter context in a task_struct:
- */
-static void
-__perf_counter_init_context(struct perf_counter_context *ctx,
- struct task_struct *task)
-{
- memset(ctx, 0, sizeof(*ctx));
- spin_lock_init(&ctx->lock);
- mutex_init(&ctx->mutex);
- INIT_LIST_HEAD(&ctx->counter_list);
- INIT_LIST_HEAD(&ctx->event_list);
- atomic_set(&ctx->refcount, 1);
- ctx->task = task;
-}
-
-static struct perf_counter_context *find_get_context(pid_t pid, int cpu)
-{
- struct perf_counter_context *ctx;
- struct perf_cpu_context *cpuctx;
- struct task_struct *task;
- unsigned long flags;
- int err;
-
- /*
- * If cpu is not a wildcard then this is a percpu counter:
- */
- if (cpu != -1) {
- /* Must be root to operate on a CPU counter: */
- if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN))
- return ERR_PTR(-EACCES);
-
- if (cpu < 0 || cpu > num_possible_cpus())
- return ERR_PTR(-EINVAL);
-
- /*
- * We could be clever and allow to attach a counter to an
- * offline CPU and activate it when the CPU comes up, but
- * that's for later.
- */
- if (!cpu_isset(cpu, cpu_online_map))
- return ERR_PTR(-ENODEV);
-
- cpuctx = &per_cpu(perf_cpu_context, cpu);
- ctx = &cpuctx->ctx;
- get_ctx(ctx);
-
- return ctx;
- }
-
- rcu_read_lock();
- if (!pid)
- task = current;
- else
- task = find_task_by_vpid(pid);
- if (task)
- get_task_struct(task);
- rcu_read_unlock();
-
- if (!task)
- return ERR_PTR(-ESRCH);
-
- /*
- * Can't attach counters to a dying task.
- */
- err = -ESRCH;
- if (task->flags & PF_EXITING)
- goto errout;
-
- /* Reuse ptrace permission checks for now. */
- err = -EACCES;
- if (!ptrace_may_access(task, PTRACE_MODE_READ))
- goto errout;
-
- retry:
- ctx = perf_lock_task_context(task, &flags);
- if (ctx) {
- unclone_ctx(ctx);
- spin_unlock_irqrestore(&ctx->lock, flags);
- }
-
- if (!ctx) {
- ctx = kmalloc(sizeof(struct perf_counter_context), GFP_KERNEL);
- err = -ENOMEM;
- if (!ctx)
- goto errout;
- __perf_counter_init_context(ctx, task);
- get_ctx(ctx);
- if (cmpxchg(&task->perf_counter_ctxp, NULL, ctx)) {
- /*
- * We raced with some other task; use
- * the context they set.
- */
- kfree(ctx);
- goto retry;
- }
- get_task_struct(task);
- }
-
- put_task_struct(task);
- return ctx;
-
- errout:
- put_task_struct(task);
- return ERR_PTR(err);
-}
-
-static void free_counter_rcu(struct rcu_head *head)
-{
- struct perf_counter *counter;
-
- counter = container_of(head, struct perf_counter, rcu_head);
- if (counter->ns)
- put_pid_ns(counter->ns);
- kfree(counter);
-}
-
-static void perf_pending_sync(struct perf_counter *counter);
-
-static void free_counter(struct perf_counter *counter)
-{
- perf_pending_sync(counter);
-
- if (!counter->parent) {
- atomic_dec(&nr_counters);
- if (counter->attr.mmap)
- atomic_dec(&nr_mmap_counters);
- if (counter->attr.comm)
- atomic_dec(&nr_comm_counters);
- if (counter->attr.task)
- atomic_dec(&nr_task_counters);
- }
-
- if (counter->output) {
- fput(counter->output->filp);
- counter->output = NULL;
- }
-
- if (counter->destroy)
- counter->destroy(counter);
-
- put_ctx(counter->ctx);
- call_rcu(&counter->rcu_head, free_counter_rcu);
-}
-
-/*
- * Called when the last reference to the file is gone.
- */
-static int perf_release(struct inode *inode, struct file *file)
-{
- struct perf_counter *counter = file->private_data;
- struct perf_counter_context *ctx = counter->ctx;
-
- file->private_data = NULL;
-
- WARN_ON_ONCE(ctx->parent_ctx);
- mutex_lock(&ctx->mutex);
- perf_counter_remove_from_context(counter);
- mutex_unlock(&ctx->mutex);
-
- mutex_lock(&counter->owner->perf_counter_mutex);
- list_del_init(&counter->owner_entry);
- mutex_unlock(&counter->owner->perf_counter_mutex);
- put_task_struct(counter->owner);
-
- free_counter(counter);
-
- return 0;
-}
-
-static int perf_counter_read_size(struct perf_counter *counter)
-{
- int entry = sizeof(u64); /* value */
- int size = 0;
- int nr = 1;
-
- if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
- size += sizeof(u64);
-
- if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
- size += sizeof(u64);
-
- if (counter->attr.read_format & PERF_FORMAT_ID)
- entry += sizeof(u64);
-
- if (counter->attr.read_format & PERF_FORMAT_GROUP) {
- nr += counter->group_leader->nr_siblings;
- size += sizeof(u64);
- }
-
- size += entry * nr;
-
- return size;
-}
-
-static u64 perf_counter_read_value(struct perf_counter *counter)
-{
- struct perf_counter *child;
- u64 total = 0;
-
- total += perf_counter_read(counter);
- list_for_each_entry(child, &counter->child_list, child_list)
- total += perf_counter_read(child);
-
- return total;
-}
-
-static int perf_counter_read_entry(struct perf_counter *counter,
- u64 read_format, char __user *buf)
-{
- int n = 0, count = 0;
- u64 values[2];
-
- values[n++] = perf_counter_read_value(counter);
- if (read_format & PERF_FORMAT_ID)
- values[n++] = primary_counter_id(counter);
-
- count = n * sizeof(u64);
-
- if (copy_to_user(buf, values, count))
- return -EFAULT;
-
- return count;
-}
-
-static int perf_counter_read_group(struct perf_counter *counter,
- u64 read_format, char __user *buf)
-{
- struct perf_counter *leader = counter->group_leader, *sub;
- int n = 0, size = 0, err = -EFAULT;
- u64 values[3];
-
- values[n++] = 1 + leader->nr_siblings;
- if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
- values[n++] = leader->total_time_enabled +
- atomic64_read(&leader->child_total_time_enabled);
- }
- if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
- values[n++] = leader->total_time_running +
- atomic64_read(&leader->child_total_time_running);
- }
-
- size = n * sizeof(u64);
-
- if (copy_to_user(buf, values, size))
- return -EFAULT;
-
- err = perf_counter_read_entry(leader, read_format, buf + size);
- if (err < 0)
- return err;
-
- size += err;
-
- list_for_each_entry(sub, &leader->sibling_list, list_entry) {
- err = perf_counter_read_entry(sub, read_format,
- buf + size);
- if (err < 0)
- return err;
-
- size += err;
- }
-
- return size;
-}
-
-static int perf_counter_read_one(struct perf_counter *counter,
- u64 read_format, char __user *buf)
-{
- u64 values[4];
- int n = 0;
-
- values[n++] = perf_counter_read_value(counter);
- if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
- values[n++] = counter->total_time_enabled +
- atomic64_read(&counter->child_total_time_enabled);
- }
- if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
- values[n++] = counter->total_time_running +
- atomic64_read(&counter->child_total_time_running);
- }
- if (read_format & PERF_FORMAT_ID)
- values[n++] = primary_counter_id(counter);
-
- if (copy_to_user(buf, values, n * sizeof(u64)))
- return -EFAULT;
-
- return n * sizeof(u64);
-}
-
-/*
- * Read the performance counter - simple non blocking version for now
- */
-static ssize_t
-perf_read_hw(struct perf_counter *counter, char __user *buf, size_t count)
-{
- u64 read_format = counter->attr.read_format;
- int ret;
-
- /*
- * Return end-of-file for a read on a counter that is in
- * error state (i.e. because it was pinned but it couldn't be
- * scheduled on to the CPU at some point).
- */
- if (counter->state == PERF_COUNTER_STATE_ERROR)
- return 0;
-
- if (count < perf_counter_read_size(counter))
- return -ENOSPC;
-
- WARN_ON_ONCE(counter->ctx->parent_ctx);
- mutex_lock(&counter->child_mutex);
- if (read_format & PERF_FORMAT_GROUP)
- ret = perf_counter_read_group(counter, read_format, buf);
- else
- ret = perf_counter_read_one(counter, read_format, buf);
- mutex_unlock(&counter->child_mutex);
-
- return ret;
-}
-
-static ssize_t
-perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
-{
- struct perf_counter *counter = file->private_data;
-
- return perf_read_hw(counter, buf, count);
-}
-
-static unsigned int perf_poll(struct file *file, poll_table *wait)
-{
- struct perf_counter *counter = file->private_data;
- struct perf_mmap_data *data;
- unsigned int events = POLL_HUP;
-
- rcu_read_lock();
- data = rcu_dereference(counter->data);
- if (data)
- events = atomic_xchg(&data->poll, 0);
- rcu_read_unlock();
-
- poll_wait(file, &counter->waitq, wait);
-
- return events;
-}
-
-static void perf_counter_reset(struct perf_counter *counter)
-{
- (void)perf_counter_read(counter);
- atomic64_set(&counter->count, 0);
- perf_counter_update_userpage(counter);
-}
-
-/*
- * Holding the top-level counter's child_mutex means that any
- * descendant process that has inherited this counter will block
- * in sync_child_counter if it goes to exit, thus satisfying the
- * task existence requirements of perf_counter_enable/disable.
- */
-static void perf_counter_for_each_child(struct perf_counter *counter,
- void (*func)(struct perf_counter *))
-{
- struct perf_counter *child;
-
- WARN_ON_ONCE(counter->ctx->parent_ctx);
- mutex_lock(&counter->child_mutex);
- func(counter);
- list_for_each_entry(child, &counter->child_list, child_list)
- func(child);
- mutex_unlock(&counter->child_mutex);
-}
-
-static void perf_counter_for_each(struct perf_counter *counter,
- void (*func)(struct perf_counter *))
-{
- struct perf_counter_context *ctx = counter->ctx;
- struct perf_counter *sibling;
-
- WARN_ON_ONCE(ctx->parent_ctx);
- mutex_lock(&ctx->mutex);
- counter = counter->group_leader;
-
- perf_counter_for_each_child(counter, func);
- func(counter);
- list_for_each_entry(sibling, &counter->sibling_list, list_entry)
- perf_counter_for_each_child(counter, func);
- mutex_unlock(&ctx->mutex);
-}
-
-static int perf_counter_period(struct perf_counter *counter, u64 __user *arg)
-{
- struct perf_counter_context *ctx = counter->ctx;
- unsigned long size;
- int ret = 0;
- u64 value;
-
- if (!counter->attr.sample_period)
- return -EINVAL;
-
- size = copy_from_user(&value, arg, sizeof(value));
- if (size != sizeof(value))
- return -EFAULT;
-
- if (!value)
- return -EINVAL;
-
- spin_lock_irq(&ctx->lock);
- if (counter->attr.freq) {
- if (value > sysctl_perf_counter_sample_rate) {
- ret = -EINVAL;
- goto unlock;
- }
-
- counter->attr.sample_freq = value;
- } else {
- counter->attr.sample_period = value;
- counter->hw.sample_period = value;
- }
-unlock:
- spin_unlock_irq(&ctx->lock);
-
- return ret;
-}
-
-int perf_counter_set_output(struct perf_counter *counter, int output_fd);
-
-static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
-{
- struct perf_counter *counter = file->private_data;
- void (*func)(struct perf_counter *);
- u32 flags = arg;
-
- switch (cmd) {
- case PERF_COUNTER_IOC_ENABLE:
- func = perf_counter_enable;
- break;
- case PERF_COUNTER_IOC_DISABLE:
- func = perf_counter_disable;
- break;
- case PERF_COUNTER_IOC_RESET:
- func = perf_counter_reset;
- break;
-
- case PERF_COUNTER_IOC_REFRESH:
- return perf_counter_refresh(counter, arg);
-
- case PERF_COUNTER_IOC_PERIOD:
- return perf_counter_period(counter, (u64 __user *)arg);
-
- case PERF_COUNTER_IOC_SET_OUTPUT:
- return perf_counter_set_output(counter, arg);
-
- default:
- return -ENOTTY;
- }
-
- if (flags & PERF_IOC_FLAG_GROUP)
- perf_counter_for_each(counter, func);
- else
- perf_counter_for_each_child(counter, func);
-
- return 0;
-}
-
-int perf_counter_task_enable(void)
-{
- struct perf_counter *counter;
-
- mutex_lock(&current->perf_counter_mutex);
- list_for_each_entry(counter, &current->perf_counter_list, owner_entry)
- perf_counter_for_each_child(counter, perf_counter_enable);
- mutex_unlock(&current->perf_counter_mutex);
-
- return 0;
-}
-
-int perf_counter_task_disable(void)
-{
- struct perf_counter *counter;
-
- mutex_lock(&current->perf_counter_mutex);
- list_for_each_entry(counter, &current->perf_counter_list, owner_entry)
- perf_counter_for_each_child(counter, perf_counter_disable);
- mutex_unlock(&current->perf_counter_mutex);
-
- return 0;
-}
-
-#ifndef PERF_COUNTER_INDEX_OFFSET
-# define PERF_COUNTER_INDEX_OFFSET 0
-#endif
-
-static int perf_counter_index(struct perf_counter *counter)
-{
- if (counter->state != PERF_COUNTER_STATE_ACTIVE)
- return 0;
-
- return counter->hw.idx + 1 - PERF_COUNTER_INDEX_OFFSET;
-}
-
-/*
- * Callers need to ensure there can be no nesting of this function, otherwise
- * the seqlock logic goes bad. We can not serialize this because the arch
- * code calls this from NMI context.
- */
-void perf_counter_update_userpage(struct perf_counter *counter)
-{
- struct perf_counter_mmap_page *userpg;
- struct perf_mmap_data *data;
-
- rcu_read_lock();
- data = rcu_dereference(counter->data);
- if (!data)
- goto unlock;
-
- userpg = data->user_page;
-
- /*
- * Disable preemption so as to not let the corresponding user-space
- * spin too long if we get preempted.
- */
- preempt_disable();
- ++userpg->lock;
- barrier();
- userpg->index = perf_counter_index(counter);
- userpg->offset = atomic64_read(&counter->count);
- if (counter->state == PERF_COUNTER_STATE_ACTIVE)
- userpg->offset -= atomic64_read(&counter->hw.prev_count);
-
- userpg->time_enabled = counter->total_time_enabled +
- atomic64_read(&counter->child_total_time_enabled);
-
- userpg->time_running = counter->total_time_running +
- atomic64_read(&counter->child_total_time_running);
-
- barrier();
- ++userpg->lock;
- preempt_enable();
-unlock:
- rcu_read_unlock();
-}
-
-static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
-{
- struct perf_counter *counter = vma->vm_file->private_data;
- struct perf_mmap_data *data;
- int ret = VM_FAULT_SIGBUS;
-
- if (vmf->flags & FAULT_FLAG_MKWRITE) {
- if (vmf->pgoff == 0)
- ret = 0;
- return ret;
- }
-
- rcu_read_lock();
- data = rcu_dereference(counter->data);
- if (!data)
- goto unlock;
-
- if (vmf->pgoff == 0) {
- vmf->page = virt_to_page(data->user_page);
- } else {
- int nr = vmf->pgoff - 1;
-
- if ((unsigned)nr > data->nr_pages)
- goto unlock;
-
- if (vmf->flags & FAULT_FLAG_WRITE)
- goto unlock;
-
- vmf->page = virt_to_page(data->data_pages[nr]);
- }
-
- get_page(vmf->page);
- vmf->page->mapping = vma->vm_file->f_mapping;
- vmf->page->index = vmf->pgoff;
-
- ret = 0;
-unlock:
- rcu_read_unlock();
-
- return ret;
-}
-
-static int perf_mmap_data_alloc(struct perf_counter *counter, int nr_pages)
-{
- struct perf_mmap_data *data;
- unsigned long size;
- int i;
-
- WARN_ON(atomic_read(&counter->mmap_count));
-
- size = sizeof(struct perf_mmap_data);
- size += nr_pages * sizeof(void *);
-
- data = kzalloc(size, GFP_KERNEL);
- if (!data)
- goto fail;
-
- data->user_page = (void *)get_zeroed_page(GFP_KERNEL);
- if (!data->user_page)
- goto fail_user_page;
-
- for (i = 0; i < nr_pages; i++) {
- data->data_pages[i] = (void *)get_zeroed_page(GFP_KERNEL);
- if (!data->data_pages[i])
- goto fail_data_pages;
- }
-
- data->nr_pages = nr_pages;
- atomic_set(&data->lock, -1);
-
- rcu_assign_pointer(counter->data, data);
-
- return 0;
-
-fail_data_pages:
- for (i--; i >= 0; i--)
- free_page((unsigned long)data->data_pages[i]);
-
- free_page((unsigned long)data->user_page);
-
-fail_user_page:
- kfree(data);
-
-fail:
- return -ENOMEM;
-}
-
-static void perf_mmap_free_page(unsigned long addr)
-{
- struct page *page = virt_to_page((void *)addr);
-
- page->mapping = NULL;
- __free_page(page);
-}
-
-static void __perf_mmap_data_free(struct rcu_head *rcu_head)
-{
- struct perf_mmap_data *data;
- int i;
-
- data = container_of(rcu_head, struct perf_mmap_data, rcu_head);
-
- perf_mmap_free_page((unsigned long)data->user_page);
- for (i = 0; i < data->nr_pages; i++)
- perf_mmap_free_page((unsigned long)data->data_pages[i]);
-
- kfree(data);
-}
-
-static void perf_mmap_data_free(struct perf_counter *counter)
-{
- struct perf_mmap_data *data = counter->data;
-
- WARN_ON(atomic_read(&counter->mmap_count));
-
- rcu_assign_pointer(counter->data, NULL);
- call_rcu(&data->rcu_head, __perf_mmap_data_free);
-}
-
-static void perf_mmap_open(struct vm_area_struct *vma)
-{
- struct perf_counter *counter = vma->vm_file->private_data;
-
- atomic_inc(&counter->mmap_count);
-}
-
-static void perf_mmap_close(struct vm_area_struct *vma)
-{
- struct perf_counter *counter = vma->vm_file->private_data;
-
- WARN_ON_ONCE(counter->ctx->parent_ctx);
- if (atomic_dec_and_mutex_lock(&counter->mmap_count, &counter->mmap_mutex)) {
- struct user_struct *user = current_user();
-
- atomic_long_sub(counter->data->nr_pages + 1, &user->locked_vm);
- vma->vm_mm->locked_vm -= counter->data->nr_locked;
- perf_mmap_data_free(counter);
- mutex_unlock(&counter->mmap_mutex);
- }
-}
-
-static struct vm_operations_struct perf_mmap_vmops = {
- .open = perf_mmap_open,
- .close = perf_mmap_close,
- .fault = perf_mmap_fault,
- .page_mkwrite = perf_mmap_fault,
-};
-
-static int perf_mmap(struct file *file, struct vm_area_struct *vma)
-{
- struct perf_counter *counter = file->private_data;
- unsigned long user_locked, user_lock_limit;
- struct user_struct *user = current_user();
- unsigned long locked, lock_limit;
- unsigned long vma_size;
- unsigned long nr_pages;
- long user_extra, extra;
- int ret = 0;
-
- if (!(vma->vm_flags & VM_SHARED))
- return -EINVAL;
-
- vma_size = vma->vm_end - vma->vm_start;
- nr_pages = (vma_size / PAGE_SIZE) - 1;
-
- /*
- * If we have data pages ensure they're a power-of-two number, so we
- * can do bitmasks instead of modulo.
- */
- if (nr_pages != 0 && !is_power_of_2(nr_pages))
- return -EINVAL;
-
- if (vma_size != PAGE_SIZE * (1 + nr_pages))
- return -EINVAL;
-
- if (vma->vm_pgoff != 0)
- return -EINVAL;
-
- WARN_ON_ONCE(counter->ctx->parent_ctx);
- mutex_lock(&counter->mmap_mutex);
- if (counter->output) {
- ret = -EINVAL;
- goto unlock;
- }
-
- if (atomic_inc_not_zero(&counter->mmap_count)) {
- if (nr_pages != counter->data->nr_pages)
- ret = -EINVAL;
- goto unlock;
- }
-
- user_extra = nr_pages + 1;
- user_lock_limit = sysctl_perf_counter_mlock >> (PAGE_SHIFT - 10);
-
- /*
- * Increase the limit linearly with more CPUs:
- */
- user_lock_limit *= num_online_cpus();
-
- user_locked = atomic_long_read(&user->locked_vm) + user_extra;
-
- extra = 0;
- if (user_locked > user_lock_limit)
- extra = user_locked - user_lock_limit;
-
- lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
- lock_limit >>= PAGE_SHIFT;
- locked = vma->vm_mm->locked_vm + extra;
-
- if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) {
- ret = -EPERM;
- goto unlock;
- }
-
- WARN_ON(counter->data);
- ret = perf_mmap_data_alloc(counter, nr_pages);
- if (ret)
- goto unlock;
-
- atomic_set(&counter->mmap_count, 1);
- atomic_long_add(user_extra, &user->locked_vm);
- vma->vm_mm->locked_vm += extra;
- counter->data->nr_locked = extra;
- if (vma->vm_flags & VM_WRITE)
- counter->data->writable = 1;
-
-unlock:
- mutex_unlock(&counter->mmap_mutex);
-
- vma->vm_flags |= VM_RESERVED;
- vma->vm_ops = &perf_mmap_vmops;
-
- return ret;
-}
-
-static int perf_fasync(int fd, struct file *filp, int on)
-{
- struct inode *inode = filp->f_path.dentry->d_inode;
- struct perf_counter *counter = filp->private_data;
- int retval;
-
- mutex_lock(&inode->i_mutex);
- retval = fasync_helper(fd, filp, on, &counter->fasync);
- mutex_unlock(&inode->i_mutex);
-
- if (retval < 0)
- return retval;
-
- return 0;
-}
-
-static const struct file_operations perf_fops = {
- .release = perf_release,
- .read = perf_read,
- .poll = perf_poll,
- .unlocked_ioctl = perf_ioctl,
- .compat_ioctl = perf_ioctl,
- .mmap = perf_mmap,
- .fasync = perf_fasync,
-};
-
-/*
- * Perf counter wakeup
- *
- * If there's data, ensure we set the poll() state and publish everything
- * to user-space before waking everybody up.
- */
-
-void perf_counter_wakeup(struct perf_counter *counter)
-{
- wake_up_all(&counter->waitq);
-
- if (counter->pending_kill) {
- kill_fasync(&counter->fasync, SIGIO, counter->pending_kill);
- counter->pending_kill = 0;
- }
-}
-
-/*
- * Pending wakeups
- *
- * Handle the case where we need to wakeup up from NMI (or rq->lock) context.
- *
- * The NMI bit means we cannot possibly take locks. Therefore, maintain a
- * single linked list and use cmpxchg() to add entries lockless.
- */
-
-static void perf_pending_counter(struct perf_pending_entry *entry)
-{
- struct perf_counter *counter = container_of(entry,
- struct perf_counter, pending);
-
- if (counter->pending_disable) {
- counter->pending_disable = 0;
- __perf_counter_disable(counter);
- }
-
- if (counter->pending_wakeup) {
- counter->pending_wakeup = 0;
- perf_counter_wakeup(counter);
- }
-}
-
-#define PENDING_TAIL ((struct perf_pending_entry *)-1UL)
-
-static DEFINE_PER_CPU(struct perf_pending_entry *, perf_pending_head) = {
- PENDING_TAIL,
-};
-
-static void perf_pending_queue(struct perf_pending_entry *entry,
- void (*func)(struct perf_pending_entry *))
-{
- struct perf_pending_entry **head;
-
- if (cmpxchg(&entry->next, NULL, PENDING_TAIL) != NULL)
- return;
-
- entry->func = func;
-
- head = &get_cpu_var(perf_pending_head);
-
- do {
- entry->next = *head;
- } while (cmpxchg(head, entry->next, entry) != entry->next);
-
- set_perf_counter_pending();
-
- put_cpu_var(perf_pending_head);
-}
-
-static int __perf_pending_run(void)
-{
- struct perf_pending_entry *list;
- int nr = 0;
-
- list = xchg(&__get_cpu_var(perf_pending_head), PENDING_TAIL);
- while (list != PENDING_TAIL) {
- void (*func)(struct perf_pending_entry *);
- struct perf_pending_entry *entry = list;
-
- list = list->next;
-
- func = entry->func;
- entry->next = NULL;
- /*
- * Ensure we observe the unqueue before we issue the wakeup,
- * so that we won't be waiting forever.
- * -- see perf_not_pending().
- */
- smp_wmb();
-
- func(entry);
- nr++;
- }
-
- return nr;
-}
-
-static inline int perf_not_pending(struct perf_counter *counter)
-{
- /*
- * If we flush on whatever cpu we run, there is a chance we don't
- * need to wait.
- */
- get_cpu();
- __perf_pending_run();
- put_cpu();
-
- /*
- * Ensure we see the proper queue state before going to sleep
- * so that we do not miss the wakeup. -- see perf_pending_handle()
- */
- smp_rmb();
- return counter->pending.next == NULL;
-}
-
-static void perf_pending_sync(struct perf_counter *counter)
-{
- wait_event(counter->waitq, perf_not_pending(counter));
-}
-
-void perf_counter_do_pending(void)
-{
- __perf_pending_run();
-}
-
-/*
- * Callchain support -- arch specific
- */
-
-__weak struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
-{
- return NULL;
-}
-
-/*
- * Output
- */
-
-struct perf_output_handle {
- struct perf_counter *counter;
- struct perf_mmap_data *data;
- unsigned long head;
- unsigned long offset;
- int nmi;
- int sample;
- int locked;
- unsigned long flags;
-};
-
-static bool perf_output_space(struct perf_mmap_data *data,
- unsigned int offset, unsigned int head)
-{
- unsigned long tail;
- unsigned long mask;
-
- if (!data->writable)
- return true;
-
- mask = (data->nr_pages << PAGE_SHIFT) - 1;
- /*
- * Userspace could choose to issue a mb() before updating the tail
- * pointer. So that all reads will be completed before the write is
- * issued.
- */
- tail = ACCESS_ONCE(data->user_page->data_tail);
- smp_rmb();
-
- offset = (offset - tail) & mask;
- head = (head - tail) & mask;
-
- if ((int)(head - offset) < 0)
- return false;
-
- return true;
-}
-
-static void perf_output_wakeup(struct perf_output_handle *handle)
-{
- atomic_set(&handle->data->poll, POLL_IN);
-
- if (handle->nmi) {
- handle->counter->pending_wakeup = 1;
- perf_pending_queue(&handle->counter->pending,
- perf_pending_counter);
- } else
- perf_counter_wakeup(handle->counter);
-}
-
-/*
- * Curious locking construct.
- *
- * We need to ensure a later event doesn't publish a head when a former
- * event isn't done writing. However since we need to deal with NMIs we
- * cannot fully serialize things.
- *
- * What we do is serialize between CPUs so we only have to deal with NMI
- * nesting on a single CPU.
- *
- * We only publish the head (and generate a wakeup) when the outer-most
- * event completes.
- */
-static void perf_output_lock(struct perf_output_handle *handle)
-{
- struct perf_mmap_data *data = handle->data;
- int cpu;
-
- handle->locked = 0;
-
- local_irq_save(handle->flags);
- cpu = smp_processor_id();
-
- if (in_nmi() && atomic_read(&data->lock) == cpu)
- return;
-
- while (atomic_cmpxchg(&data->lock, -1, cpu) != -1)
- cpu_relax();
-
- handle->locked = 1;
-}
-
-static void perf_output_unlock(struct perf_output_handle *handle)
-{
- struct perf_mmap_data *data = handle->data;
- unsigned long head;
- int cpu;
-
- data->done_head = data->head;
-
- if (!handle->locked)
- goto out;
-
-again:
- /*
- * The xchg implies a full barrier that ensures all writes are done
- * before we publish the new head, matched by a rmb() in userspace when
- * reading this position.
- */
- while ((head = atomic_long_xchg(&data->done_head, 0)))
- data->user_page->data_head = head;
-
- /*
- * NMI can happen here, which means we can miss a done_head update.
- */
-
- cpu = atomic_xchg(&data->lock, -1);
- WARN_ON_ONCE(cpu != smp_processor_id());
-
- /*
- * Therefore we have to validate we did not indeed do so.
- */
- if (unlikely(atomic_long_read(&data->done_head))) {
- /*
- * Since we had it locked, we can lock it again.
- */
- while (atomic_cmpxchg(&data->lock, -1, cpu) != -1)
- cpu_relax();
-
- goto again;
- }
-
- if (atomic_xchg(&data->wakeup, 0))
- perf_output_wakeup(handle);
-out:
- local_irq_restore(handle->flags);
-}
-
-static void perf_output_copy(struct perf_output_handle *handle,
- const void *buf, unsigned int len)
-{
- unsigned int pages_mask;
- unsigned int offset;
- unsigned int size;
- void **pages;
-
- offset = handle->offset;
- pages_mask = handle->data->nr_pages - 1;
- pages = handle->data->data_pages;
-
- do {
- unsigned int page_offset;
- int nr;
-
- nr = (offset >> PAGE_SHIFT) & pages_mask;
- page_offset = offset & (PAGE_SIZE - 1);
- size = min_t(unsigned int, PAGE_SIZE - page_offset, len);
-
- memcpy(pages[nr] + page_offset, buf, size);
-
- len -= size;
- buf += size;
- offset += size;
- } while (len);
-
- handle->offset = offset;
-
- /*
- * Check we didn't copy past our reservation window, taking the
- * possible unsigned int wrap into account.
- */
- WARN_ON_ONCE(((long)(handle->head - handle->offset)) < 0);
-}
-
-#define perf_output_put(handle, x) \
- perf_output_copy((handle), &(x), sizeof(x))
-
-static int perf_output_begin(struct perf_output_handle *handle,
- struct perf_counter *counter, unsigned int size,
- int nmi, int sample)
-{
- struct perf_counter *output_counter;
- struct perf_mmap_data *data;
- unsigned int offset, head;
- int have_lost;
- struct {
- struct perf_event_header header;
- u64 id;
- u64 lost;
- } lost_event;
-
- rcu_read_lock();
- /*
- * For inherited counters we send all the output towards the parent.
- */
- if (counter->parent)
- counter = counter->parent;
-
- output_counter = rcu_dereference(counter->output);
- if (output_counter)
- counter = output_counter;
-
- data = rcu_dereference(counter->data);
- if (!data)
- goto out;
-
- handle->data = data;
- handle->counter = counter;
- handle->nmi = nmi;
- handle->sample = sample;
-
- if (!data->nr_pages)
- goto fail;
-
- have_lost = atomic_read(&data->lost);
- if (have_lost)
- size += sizeof(lost_event);
-
- perf_output_lock(handle);
-
- do {
- offset = head = atomic_long_read(&data->head);
- head += size;
- if (unlikely(!perf_output_space(data, offset, head)))
- goto fail;
- } while (atomic_long_cmpxchg(&data->head, offset, head) != offset);
-
- handle->offset = offset;
- handle->head = head;
-
- if ((offset >> PAGE_SHIFT) != (head >> PAGE_SHIFT))
- atomic_set(&data->wakeup, 1);
-
- if (have_lost) {
- lost_event.header.type = PERF_EVENT_LOST;
- lost_event.header.misc = 0;
- lost_event.header.size = sizeof(lost_event);
- lost_event.id = counter->id;
- lost_event.lost = atomic_xchg(&data->lost, 0);
-
- perf_output_put(handle, lost_event);
- }
-
- return 0;
-
-fail:
- atomic_inc(&data->lost);
- perf_output_unlock(handle);
-out:
- rcu_read_unlock();
-
- return -ENOSPC;
-}
-
-static void perf_output_end(struct perf_output_handle *handle)
-{
- struct perf_counter *counter = handle->counter;
- struct perf_mmap_data *data = handle->data;
-
- int wakeup_events = counter->attr.wakeup_events;
-
- if (handle->sample && wakeup_events) {
- int events = atomic_inc_return(&data->events);
- if (events >= wakeup_events) {
- atomic_sub(wakeup_events, &data->events);
- atomic_set(&data->wakeup, 1);
- }
- }
-
- perf_output_unlock(handle);
- rcu_read_unlock();
-}
-
-static u32 perf_counter_pid(struct perf_counter *counter, struct task_struct *p)
-{
- /*
- * only top level counters have the pid namespace they were created in
- */
- if (counter->parent)
- counter = counter->parent;
-
- return task_tgid_nr_ns(p, counter->ns);
-}
-
-static u32 perf_counter_tid(struct perf_counter *counter, struct task_struct *p)
-{
- /*
- * only top level counters have the pid namespace they were created in
- */
- if (counter->parent)
- counter = counter->parent;
-
- return task_pid_nr_ns(p, counter->ns);
-}
-
-static void perf_output_read_one(struct perf_output_handle *handle,
- struct perf_counter *counter)
-{
- u64 read_format = counter->attr.read_format;
- u64 values[4];
- int n = 0;
-
- values[n++] = atomic64_read(&counter->count);
- if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
- values[n++] = counter->total_time_enabled +
- atomic64_read(&counter->child_total_time_enabled);
- }
- if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
- values[n++] = counter->total_time_running +
- atomic64_read(&counter->child_total_time_running);
- }
- if (read_format & PERF_FORMAT_ID)
- values[n++] = primary_counter_id(counter);
-
- perf_output_copy(handle, values, n * sizeof(u64));
-}
-
-/*
- * XXX PERF_FORMAT_GROUP vs inherited counters seems difficult.
- */
-static void perf_output_read_group(struct perf_output_handle *handle,
- struct perf_counter *counter)
-{
- struct perf_counter *leader = counter->group_leader, *sub;
- u64 read_format = counter->attr.read_format;
- u64 values[5];
- int n = 0;
-
- values[n++] = 1 + leader->nr_siblings;
-
- if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
- values[n++] = leader->total_time_enabled;
-
- if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
- values[n++] = leader->total_time_running;
-
- if (leader != counter)
- leader->pmu->read(leader);
-
- values[n++] = atomic64_read(&leader->count);
- if (read_format & PERF_FORMAT_ID)
- values[n++] = primary_counter_id(leader);
-
- perf_output_copy(handle, values, n * sizeof(u64));
-
- list_for_each_entry(sub, &leader->sibling_list, list_entry) {
- n = 0;
-
- if (sub != counter)
- sub->pmu->read(sub);
-
- values[n++] = atomic64_read(&sub->count);
- if (read_format & PERF_FORMAT_ID)
- values[n++] = primary_counter_id(sub);
-
- perf_output_copy(handle, values, n * sizeof(u64));
- }
-}
-
-static void perf_output_read(struct perf_output_handle *handle,
- struct perf_counter *counter)
-{
- if (counter->attr.read_format & PERF_FORMAT_GROUP)
- perf_output_read_group(handle, counter);
- else
- perf_output_read_one(handle, counter);
-}
-
-void perf_counter_output(struct perf_counter *counter, int nmi,
- struct perf_sample_data *data)
-{
- int ret;
- u64 sample_type = counter->attr.sample_type;
- struct perf_output_handle handle;
- struct perf_event_header header;
- u64 ip;
- struct {
- u32 pid, tid;
- } tid_entry;
- struct perf_callchain_entry *callchain = NULL;
- int callchain_size = 0;
- u64 time;
- struct {
- u32 cpu, reserved;
- } cpu_entry;
-
- header.type = PERF_EVENT_SAMPLE;
- header.size = sizeof(header);
-
- header.misc = 0;
- header.misc |= perf_misc_flags(data->regs);
-
- if (sample_type & PERF_SAMPLE_IP) {
- ip = perf_instruction_pointer(data->regs);
- header.size += sizeof(ip);
- }
-
- if (sample_type & PERF_SAMPLE_TID) {
- /* namespace issues */
- tid_entry.pid = perf_counter_pid(counter, current);
- tid_entry.tid = perf_counter_tid(counter, current);
-
- header.size += sizeof(tid_entry);
- }
-
- if (sample_type & PERF_SAMPLE_TIME) {
- /*
- * Maybe do better on x86 and provide cpu_clock_nmi()
- */
- time = sched_clock();
-
- header.size += sizeof(u64);
- }
-
- if (sample_type & PERF_SAMPLE_ADDR)
- header.size += sizeof(u64);
-
- if (sample_type & PERF_SAMPLE_ID)
- header.size += sizeof(u64);
-
- if (sample_type & PERF_SAMPLE_STREAM_ID)
- header.size += sizeof(u64);
-
- if (sample_type & PERF_SAMPLE_CPU) {
- header.size += sizeof(cpu_entry);
-
- cpu_entry.cpu = raw_smp_processor_id();
- cpu_entry.reserved = 0;
- }
-
- if (sample_type & PERF_SAMPLE_PERIOD)
- header.size += sizeof(u64);
-
- if (sample_type & PERF_SAMPLE_READ)
- header.size += perf_counter_read_size(counter);
-
- if (sample_type & PERF_SAMPLE_CALLCHAIN) {
- callchain = perf_callchain(data->regs);
-
- if (callchain) {
- callchain_size = (1 + callchain->nr) * sizeof(u64);
- header.size += callchain_size;
- } else
- header.size += sizeof(u64);
- }
-
- if (sample_type & PERF_SAMPLE_RAW) {
- int size = sizeof(u32);
-
- if (data->raw)
- size += data->raw->size;
- else
- size += sizeof(u32);
-
- WARN_ON_ONCE(size & (sizeof(u64)-1));
- header.size += size;
- }
-
- ret = perf_output_begin(&handle, counter, header.size, nmi, 1);
- if (ret)
- return;
-
- perf_output_put(&handle, header);
-
- if (sample_type & PERF_SAMPLE_IP)
- perf_output_put(&handle, ip);
-
- if (sample_type & PERF_SAMPLE_TID)
- perf_output_put(&handle, tid_entry);
-
- if (sample_type & PERF_SAMPLE_TIME)
- perf_output_put(&handle, time);
-
- if (sample_type & PERF_SAMPLE_ADDR)
- perf_output_put(&handle, data->addr);
-
- if (sample_type & PERF_SAMPLE_ID) {
- u64 id = primary_counter_id(counter);
-
- perf_output_put(&handle, id);
- }
-
- if (sample_type & PERF_SAMPLE_STREAM_ID)
- perf_output_put(&handle, counter->id);
-
- if (sample_type & PERF_SAMPLE_CPU)
- perf_output_put(&handle, cpu_entry);
-
- if (sample_type & PERF_SAMPLE_PERIOD)
- perf_output_put(&handle, data->period);
-
- if (sample_type & PERF_SAMPLE_READ)
- perf_output_read(&handle, counter);
-
- if (sample_type & PERF_SAMPLE_CALLCHAIN) {
- if (callchain)
- perf_output_copy(&handle, callchain, callchain_size);
- else {
- u64 nr = 0;
- perf_output_put(&handle, nr);
- }
- }
-
- if (sample_type & PERF_SAMPLE_RAW) {
- if (data->raw) {
- perf_output_put(&handle, data->raw->size);
- perf_output_copy(&handle, data->raw->data, data->raw->size);
- } else {
- struct {
- u32 size;
- u32 data;
- } raw = {
- .size = sizeof(u32),
- .data = 0,
- };
- perf_output_put(&handle, raw);
- }
- }
-
- perf_output_end(&handle);
-}
-
-/*
- * read event
- */
-
-struct perf_read_event {
- struct perf_event_header header;
-
- u32 pid;
- u32 tid;
-};
-
-static void
-perf_counter_read_event(struct perf_counter *counter,
- struct task_struct *task)
-{
- struct perf_output_handle handle;
- struct perf_read_event event = {
- .header = {
- .type = PERF_EVENT_READ,
- .misc = 0,
- .size = sizeof(event) + perf_counter_read_size(counter),
- },
- .pid = perf_counter_pid(counter, task),
- .tid = perf_counter_tid(counter, task),
- };
- int ret;
-
- ret = perf_output_begin(&handle, counter, event.header.size, 0, 0);
- if (ret)
- return;
-
- perf_output_put(&handle, event);
- perf_output_read(&handle, counter);
-
- perf_output_end(&handle);
-}
-
-/*
- * task tracking -- fork/exit
- *
- * enabled by: attr.comm | attr.mmap | attr.task
- */
-
-struct perf_task_event {
- struct task_struct *task;
- struct perf_counter_context *task_ctx;
-
- struct {
- struct perf_event_header header;
-
- u32 pid;
- u32 ppid;
- u32 tid;
- u32 ptid;
- } event;
-};
-
-static void perf_counter_task_output(struct perf_counter *counter,
- struct perf_task_event *task_event)
-{
- struct perf_output_handle handle;
- int size = task_event->event.header.size;
- struct task_struct *task = task_event->task;
- int ret = perf_output_begin(&handle, counter, size, 0, 0);
-
- if (ret)
- return;
-
- task_event->event.pid = perf_counter_pid(counter, task);
- task_event->event.ppid = perf_counter_pid(counter, current);
-
- task_event->event.tid = perf_counter_tid(counter, task);
- task_event->event.ptid = perf_counter_tid(counter, current);
-
- perf_output_put(&handle, task_event->event);
- perf_output_end(&handle);
-}
-
-static int perf_counter_task_match(struct perf_counter *counter)
-{
- if (counter->attr.comm || counter->attr.mmap || counter->attr.task)
- return 1;
-
- return 0;
-}
-
-static void perf_counter_task_ctx(struct perf_counter_context *ctx,
- struct perf_task_event *task_event)
-{
- struct perf_counter *counter;
-
- if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
- return;
-
- rcu_read_lock();
- list_for_each_entry_rcu(counter, &ctx->event_list, event_entry) {
- if (perf_counter_task_match(counter))
- perf_counter_task_output(counter, task_event);
- }
- rcu_read_unlock();
-}
-
-static void perf_counter_task_event(struct perf_task_event *task_event)
-{
- struct perf_cpu_context *cpuctx;
- struct perf_counter_context *ctx = task_event->task_ctx;
-
- cpuctx = &get_cpu_var(perf_cpu_context);
- perf_counter_task_ctx(&cpuctx->ctx, task_event);
- put_cpu_var(perf_cpu_context);
-
- rcu_read_lock();
- if (!ctx)
- ctx = rcu_dereference(task_event->task->perf_counter_ctxp);
- if (ctx)
- perf_counter_task_ctx(ctx, task_event);
- rcu_read_unlock();
-}
-
-static void perf_counter_task(struct task_struct *task,
- struct perf_counter_context *task_ctx,
- int new)
-{
- struct perf_task_event task_event;
-
- if (!atomic_read(&nr_comm_counters) &&
- !atomic_read(&nr_mmap_counters) &&
- !atomic_read(&nr_task_counters))
- return;
-
- task_event = (struct perf_task_event){
- .task = task,
- .task_ctx = task_ctx,
- .event = {
- .header = {
- .type = new ? PERF_EVENT_FORK : PERF_EVENT_EXIT,
- .misc = 0,
- .size = sizeof(task_event.event),
- },
- /* .pid */
- /* .ppid */
- /* .tid */
- /* .ptid */
- },
- };
-
- perf_counter_task_event(&task_event);
-}
-
-void perf_counter_fork(struct task_struct *task)
-{
- perf_counter_task(task, NULL, 1);
-}
-
-/*
- * comm tracking
- */
-
-struct perf_comm_event {
- struct task_struct *task;
- char *comm;
- int comm_size;
-
- struct {
- struct perf_event_header header;
-
- u32 pid;
- u32 tid;
- } event;
-};
-
-static void perf_counter_comm_output(struct perf_counter *counter,
- struct perf_comm_event *comm_event)
-{
- struct perf_output_handle handle;
- int size = comm_event->event.header.size;
- int ret = perf_output_begin(&handle, counter, size, 0, 0);
-
- if (ret)
- return;
-
- comm_event->event.pid = perf_counter_pid(counter, comm_event->task);
- comm_event->event.tid = perf_counter_tid(counter, comm_event->task);
-
- perf_output_put(&handle, comm_event->event);
- perf_output_copy(&handle, comm_event->comm,
- comm_event->comm_size);
- perf_output_end(&handle);
-}
-
-static int perf_counter_comm_match(struct perf_counter *counter)
-{
- if (counter->attr.comm)
- return 1;
-
- return 0;
-}
-
-static void perf_counter_comm_ctx(struct perf_counter_context *ctx,
- struct perf_comm_event *comm_event)
-{
- struct perf_counter *counter;
-
- if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
- return;
-
- rcu_read_lock();
- list_for_each_entry_rcu(counter, &ctx->event_list, event_entry) {
- if (perf_counter_comm_match(counter))
- perf_counter_comm_output(counter, comm_event);
- }
- rcu_read_unlock();
-}
-
-static void perf_counter_comm_event(struct perf_comm_event *comm_event)
-{
- struct perf_cpu_context *cpuctx;
- struct perf_counter_context *ctx;
- unsigned int size;
- char comm[TASK_COMM_LEN];
-
- memset(comm, 0, sizeof(comm));
- strncpy(comm, comm_event->task->comm, sizeof(comm));
- size = ALIGN(strlen(comm)+1, sizeof(u64));
-
- comm_event->comm = comm;
- comm_event->comm_size = size;
-
- comm_event->event.header.size = sizeof(comm_event->event) + size;
-
- cpuctx = &get_cpu_var(perf_cpu_context);
- perf_counter_comm_ctx(&cpuctx->ctx, comm_event);
- put_cpu_var(perf_cpu_context);
-
- rcu_read_lock();
- /*
- * doesn't really matter which of the child contexts the
- * events ends up in.
- */
- ctx = rcu_dereference(current->perf_counter_ctxp);
- if (ctx)
- perf_counter_comm_ctx(ctx, comm_event);
- rcu_read_unlock();
-}
-
-void perf_counter_comm(struct task_struct *task)
-{
- struct perf_comm_event comm_event;
-
- if (task->perf_counter_ctxp)
- perf_counter_enable_on_exec(task);
-
- if (!atomic_read(&nr_comm_counters))
- return;
-
- comm_event = (struct perf_comm_event){
- .task = task,
- /* .comm */
- /* .comm_size */
- .event = {
- .header = {
- .type = PERF_EVENT_COMM,
- .misc = 0,
- /* .size */
- },
- /* .pid */
- /* .tid */
- },
- };
-
- perf_counter_comm_event(&comm_event);
-}
-
-/*
- * mmap tracking
- */
-
-struct perf_mmap_event {
- struct vm_area_struct *vma;
-
- const char *file_name;
- int file_size;
-
- struct {
- struct perf_event_header header;
-
- u32 pid;
- u32 tid;
- u64 start;
- u64 len;
- u64 pgoff;
- } event;
-};
-
-static void perf_counter_mmap_output(struct perf_counter *counter,
- struct perf_mmap_event *mmap_event)
-{
- struct perf_output_handle handle;
- int size = mmap_event->event.header.size;
- int ret = perf_output_begin(&handle, counter, size, 0, 0);
-
- if (ret)
- return;
-
- mmap_event->event.pid = perf_counter_pid(counter, current);
- mmap_event->event.tid = perf_counter_tid(counter, current);
-
- perf_output_put(&handle, mmap_event->event);
- perf_output_copy(&handle, mmap_event->file_name,
- mmap_event->file_size);
- perf_output_end(&handle);
-}
-
-static int perf_counter_mmap_match(struct perf_counter *counter,
- struct perf_mmap_event *mmap_event)
-{
- if (counter->attr.mmap)
- return 1;
-
- return 0;
-}
-
-static void perf_counter_mmap_ctx(struct perf_counter_context *ctx,
- struct perf_mmap_event *mmap_event)
-{
- struct perf_counter *counter;
-
- if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
- return;
-
- rcu_read_lock();
- list_for_each_entry_rcu(counter, &ctx->event_list, event_entry) {
- if (perf_counter_mmap_match(counter, mmap_event))
- perf_counter_mmap_output(counter, mmap_event);
- }
- rcu_read_unlock();
-}
-
-static void perf_counter_mmap_event(struct perf_mmap_event *mmap_event)
-{
- struct perf_cpu_context *cpuctx;
- struct perf_counter_context *ctx;
- struct vm_area_struct *vma = mmap_event->vma;
- struct file *file = vma->vm_file;
- unsigned int size;
- char tmp[16];
- char *buf = NULL;
- const char *name;
-
- memset(tmp, 0, sizeof(tmp));
-
- if (file) {
- /*
- * d_path works from the end of the buffer backwards, so we
- * need to add enough zero bytes after the string to handle
- * the 64bit alignment we do later.
- */
- buf = kzalloc(PATH_MAX + sizeof(u64), GFP_KERNEL);
- if (!buf) {
- name = strncpy(tmp, "//enomem", sizeof(tmp));
- goto got_name;
- }
- name = d_path(&file->f_path, buf, PATH_MAX);
- if (IS_ERR(name)) {
- name = strncpy(tmp, "//toolong", sizeof(tmp));
- goto got_name;
- }
- } else {
- if (arch_vma_name(mmap_event->vma)) {
- name = strncpy(tmp, arch_vma_name(mmap_event->vma),
- sizeof(tmp));
- goto got_name;
- }
-
- if (!vma->vm_mm) {
- name = strncpy(tmp, "[vdso]", sizeof(tmp));
- goto got_name;
- }
-
- name = strncpy(tmp, "//anon", sizeof(tmp));
- goto got_name;
- }
-
-got_name:
- size = ALIGN(strlen(name)+1, sizeof(u64));
-
- mmap_event->file_name = name;
- mmap_event->file_size = size;
-
- mmap_event->event.header.size = sizeof(mmap_event->event) + size;
-
- cpuctx = &get_cpu_var(perf_cpu_context);
- perf_counter_mmap_ctx(&cpuctx->ctx, mmap_event);
- put_cpu_var(perf_cpu_context);
-
- rcu_read_lock();
- /*
- * doesn't really matter which of the child contexts the
- * events ends up in.
- */
- ctx = rcu_dereference(current->perf_counter_ctxp);
- if (ctx)
- perf_counter_mmap_ctx(ctx, mmap_event);
- rcu_read_unlock();
-
- kfree(buf);
-}
-
-void __perf_counter_mmap(struct vm_area_struct *vma)
-{
- struct perf_mmap_event mmap_event;
-
- if (!atomic_read(&nr_mmap_counters))
- return;
-
- mmap_event = (struct perf_mmap_event){
- .vma = vma,
- /* .file_name */
- /* .file_size */
- .event = {
- .header = {
- .type = PERF_EVENT_MMAP,
- .misc = 0,
- /* .size */
- },
- /* .pid */
- /* .tid */
- .start = vma->vm_start,
- .len = vma->vm_end - vma->vm_start,
- .pgoff = vma->vm_pgoff,
- },
- };
-
- perf_counter_mmap_event(&mmap_event);
-}
-
-/*
- * IRQ throttle logging
- */
-
-static void perf_log_throttle(struct perf_counter *counter, int enable)
-{
- struct perf_output_handle handle;
- int ret;
-
- struct {
- struct perf_event_header header;
- u64 time;
- u64 id;
- u64 stream_id;
- } throttle_event = {
- .header = {
- .type = PERF_EVENT_THROTTLE,
- .misc = 0,
- .size = sizeof(throttle_event),
- },
- .time = sched_clock(),
- .id = primary_counter_id(counter),
- .stream_id = counter->id,
- };
-
- if (enable)
- throttle_event.header.type = PERF_EVENT_UNTHROTTLE;
-
- ret = perf_output_begin(&handle, counter, sizeof(throttle_event), 1, 0);
- if (ret)
- return;
-
- perf_output_put(&handle, throttle_event);
- perf_output_end(&handle);
-}
-
-/*
- * Generic counter overflow handling, sampling.
- */
-
-int perf_counter_overflow(struct perf_counter *counter, int nmi,
- struct perf_sample_data *data)
-{
- int events = atomic_read(&counter->event_limit);
- int throttle = counter->pmu->unthrottle != NULL;
- struct hw_perf_counter *hwc = &counter->hw;
- int ret = 0;
-
- if (!throttle) {
- hwc->interrupts++;
- } else {
- if (hwc->interrupts != MAX_INTERRUPTS) {
- hwc->interrupts++;
- if (HZ * hwc->interrupts >
- (u64)sysctl_perf_counter_sample_rate) {
- hwc->interrupts = MAX_INTERRUPTS;
- perf_log_throttle(counter, 0);
- ret = 1;
- }
- } else {
- /*
- * Keep re-disabling counters even though on the previous
- * pass we disabled it - just in case we raced with a
- * sched-in and the counter got enabled again:
- */
- ret = 1;
- }
- }
-
- if (counter->attr.freq) {
- u64 now = sched_clock();
- s64 delta = now - hwc->freq_stamp;
-
- hwc->freq_stamp = now;
-
- if (delta > 0 && delta < TICK_NSEC)
- perf_adjust_period(counter, NSEC_PER_SEC / (int)delta);
- }
-
- /*
- * XXX event_limit might not quite work as expected on inherited
- * counters
- */
-
- counter->pending_kill = POLL_IN;
- if (events && atomic_dec_and_test(&counter->event_limit)) {
- ret = 1;
- counter->pending_kill = POLL_HUP;
- if (nmi) {
- counter->pending_disable = 1;
- perf_pending_queue(&counter->pending,
- perf_pending_counter);
- } else
- perf_counter_disable(counter);
- }
-
- perf_counter_output(counter, nmi, data);
- return ret;
-}
-
-/*
- * Generic software counter infrastructure
- */
-
-/*
- * We directly increment counter->count and keep a second value in
- * counter->hw.period_left to count intervals. This period counter
- * is kept in the range [-sample_period, 0] so that we can use the
- * sign as trigger.
- */
-
-static u64 perf_swcounter_set_period(struct perf_counter *counter)
-{
- struct hw_perf_counter *hwc = &counter->hw;
- u64 period = hwc->last_period;
- u64 nr, offset;
- s64 old, val;
-
- hwc->last_period = hwc->sample_period;
-
-again:
- old = val = atomic64_read(&hwc->period_left);
- if (val < 0)
- return 0;
-
- nr = div64_u64(period + val, period);
- offset = nr * period;
- val -= offset;
- if (atomic64_cmpxchg(&hwc->period_left, old, val) != old)
- goto again;
-
- return nr;
-}
-
-static void perf_swcounter_overflow(struct perf_counter *counter,
- int nmi, struct perf_sample_data *data)
-{
- struct hw_perf_counter *hwc = &counter->hw;
- u64 overflow;
-
- data->period = counter->hw.last_period;
- overflow = perf_swcounter_set_period(counter);
-
- if (hwc->interrupts == MAX_INTERRUPTS)
- return;
-
- for (; overflow; overflow--) {
- if (perf_counter_overflow(counter, nmi, data)) {
- /*
- * We inhibit the overflow from happening when
- * hwc->interrupts == MAX_INTERRUPTS.
- */
- break;
- }
- }
-}
-
-static void perf_swcounter_unthrottle(struct perf_counter *counter)
-{
- /*
- * Nothing to do, we already reset hwc->interrupts.
- */
-}
-
-static void perf_swcounter_add(struct perf_counter *counter, u64 nr,
- int nmi, struct perf_sample_data *data)
-{
- struct hw_perf_counter *hwc = &counter->hw;
-
- atomic64_add(nr, &counter->count);
-
- if (!hwc->sample_period)
- return;
-
- if (!data->regs)
- return;
-
- if (!atomic64_add_negative(nr, &hwc->period_left))
- perf_swcounter_overflow(counter, nmi, data);
-}
-
-static int perf_swcounter_is_counting(struct perf_counter *counter)
-{
- /*
- * The counter is active, we're good!
- */
- if (counter->state == PERF_COUNTER_STATE_ACTIVE)
- return 1;
-
- /*
- * The counter is off/error, not counting.
- */
- if (counter->state != PERF_COUNTER_STATE_INACTIVE)
- return 0;
-
- /*
- * The counter is inactive, if the context is active
- * we're part of a group that didn't make it on the 'pmu',
- * not counting.
- */
- if (counter->ctx->is_active)
- return 0;
-
- /*
- * We're inactive and the context is too, this means the
- * task is scheduled out, we're counting events that happen
- * to us, like migration events.
- */
- return 1;
-}
-
-static int perf_swcounter_match(struct perf_counter *counter,
- enum perf_type_id type,
- u32 event, struct pt_regs *regs)
-{
- if (!perf_swcounter_is_counting(counter))
- return 0;
-
- if (counter->attr.type != type)
- return 0;
- if (counter->attr.config != event)
- return 0;
-
- if (regs) {
- if (counter->attr.exclude_user && user_mode(regs))
- return 0;
-
- if (counter->attr.exclude_kernel && !user_mode(regs))
- return 0;
- }
-
- return 1;
-}
-
-static void perf_swcounter_ctx_event(struct perf_counter_context *ctx,
- enum perf_type_id type,
- u32 event, u64 nr, int nmi,
- struct perf_sample_data *data)
-{
- struct perf_counter *counter;
-
- if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
- return;
-
- rcu_read_lock();
- list_for_each_entry_rcu(counter, &ctx->event_list, event_entry) {
- if (perf_swcounter_match(counter, type, event, data->regs))
- perf_swcounter_add(counter, nr, nmi, data);
- }
- rcu_read_unlock();
-}
-
-static int *perf_swcounter_recursion_context(struct perf_cpu_context *cpuctx)
-{
- if (in_nmi())
- return &cpuctx->recursion[3];
-
- if (in_irq())
- return &cpuctx->recursion[2];
-
- if (in_softirq())
- return &cpuctx->recursion[1];
-
- return &cpuctx->recursion[0];
-}
-
-static void do_perf_swcounter_event(enum perf_type_id type, u32 event,
- u64 nr, int nmi,
- struct perf_sample_data *data)
-{
- struct perf_cpu_context *cpuctx = &get_cpu_var(perf_cpu_context);
- int *recursion = perf_swcounter_recursion_context(cpuctx);
- struct perf_counter_context *ctx;
-
- if (*recursion)
- goto out;
-
- (*recursion)++;
- barrier();
-
- perf_swcounter_ctx_event(&cpuctx->ctx, type, event,
- nr, nmi, data);
- rcu_read_lock();
- /*
- * doesn't really matter which of the child contexts the
- * events ends up in.
- */
- ctx = rcu_dereference(current->perf_counter_ctxp);
- if (ctx)
- perf_swcounter_ctx_event(ctx, type, event, nr, nmi, data);
- rcu_read_unlock();
-
- barrier();
- (*recursion)--;
-
-out:
- put_cpu_var(perf_cpu_context);
-}
-
-void __perf_swcounter_event(u32 event, u64 nr, int nmi,
- struct pt_regs *regs, u64 addr)
-{
- struct perf_sample_data data = {
- .regs = regs,
- .addr = addr,
- };
-
- do_perf_swcounter_event(PERF_TYPE_SOFTWARE, event, nr, nmi, &data);
-}
-
-static void perf_swcounter_read(struct perf_counter *counter)
-{
-}
-
-static int perf_swcounter_enable(struct perf_counter *counter)
-{
- struct hw_perf_counter *hwc = &counter->hw;
-
- if (hwc->sample_period) {
- hwc->last_period = hwc->sample_period;
- perf_swcounter_set_period(counter);
- }
- return 0;
-}
-
-static void perf_swcounter_disable(struct perf_counter *counter)
-{
-}
-
-static const struct pmu perf_ops_generic = {
- .enable = perf_swcounter_enable,
- .disable = perf_swcounter_disable,
- .read = perf_swcounter_read,
- .unthrottle = perf_swcounter_unthrottle,
-};
-
-/*
- * hrtimer based swcounter callback
- */
-
-static enum hrtimer_restart perf_swcounter_hrtimer(struct hrtimer *hrtimer)
-{
- enum hrtimer_restart ret = HRTIMER_RESTART;
- struct perf_sample_data data;
- struct perf_counter *counter;
- u64 period;
-
- counter = container_of(hrtimer, struct perf_counter, hw.hrtimer);
- counter->pmu->read(counter);
-
- data.addr = 0;
- data.regs = get_irq_regs();
- /*
- * In case we exclude kernel IPs or are somehow not in interrupt
- * context, provide the next best thing, the user IP.
- */
- if ((counter->attr.exclude_kernel || !data.regs) &&
- !counter->attr.exclude_user)
- data.regs = task_pt_regs(current);
-
- if (data.regs) {
- if (perf_counter_overflow(counter, 0, &data))
- ret = HRTIMER_NORESTART;
- }
-
- period = max_t(u64, 10000, counter->hw.sample_period);
- hrtimer_forward_now(hrtimer, ns_to_ktime(period));
-
- return ret;
-}
-
-/*
- * Software counter: cpu wall time clock
- */
-
-static void cpu_clock_perf_counter_update(struct perf_counter *counter)
-{
- int cpu = raw_smp_processor_id();
- s64 prev;
- u64 now;
-
- now = cpu_clock(cpu);
- prev = atomic64_read(&counter->hw.prev_count);
- atomic64_set(&counter->hw.prev_count, now);
- atomic64_add(now - prev, &counter->count);
-}
-
-static int cpu_clock_perf_counter_enable(struct perf_counter *counter)
-{
- struct hw_perf_counter *hwc = &counter->hw;
- int cpu = raw_smp_processor_id();
-
- atomic64_set(&hwc->prev_count, cpu_clock(cpu));
- hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
- hwc->hrtimer.function = perf_swcounter_hrtimer;
- if (hwc->sample_period) {
- u64 period = max_t(u64, 10000, hwc->sample_period);
- __hrtimer_start_range_ns(&hwc->hrtimer,
- ns_to_ktime(period), 0,
- HRTIMER_MODE_REL, 0);
- }
-
- return 0;
-}
-
-static void cpu_clock_perf_counter_disable(struct perf_counter *counter)
-{
- if (counter->hw.sample_period)
- hrtimer_cancel(&counter->hw.hrtimer);
- cpu_clock_perf_counter_update(counter);
-}
-
-static void cpu_clock_perf_counter_read(struct perf_counter *counter)
-{
- cpu_clock_perf_counter_update(counter);
-}
-
-static const struct pmu perf_ops_cpu_clock = {
- .enable = cpu_clock_perf_counter_enable,
- .disable = cpu_clock_perf_counter_disable,
- .read = cpu_clock_perf_counter_read,
-};
-
-/*
- * Software counter: task time clock
- */
-
-static void task_clock_perf_counter_update(struct perf_counter *counter, u64 now)
-{
- u64 prev;
- s64 delta;
-
- prev = atomic64_xchg(&counter->hw.prev_count, now);
- delta = now - prev;
- atomic64_add(delta, &counter->count);
-}
-
-static int task_clock_perf_counter_enable(struct perf_counter *counter)
-{
- struct hw_perf_counter *hwc = &counter->hw;
- u64 now;
-
- now = counter->ctx->time;
-
- atomic64_set(&hwc->prev_count, now);
- hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
- hwc->hrtimer.function = perf_swcounter_hrtimer;
- if (hwc->sample_period) {
- u64 period = max_t(u64, 10000, hwc->sample_period);
- __hrtimer_start_range_ns(&hwc->hrtimer,
- ns_to_ktime(period), 0,
- HRTIMER_MODE_REL, 0);
- }
-
- return 0;
-}
-
-static void task_clock_perf_counter_disable(struct perf_counter *counter)
-{
- if (counter->hw.sample_period)
- hrtimer_cancel(&counter->hw.hrtimer);
- task_clock_perf_counter_update(counter, counter->ctx->time);
-
-}
-
-static void task_clock_perf_counter_read(struct perf_counter *counter)
-{
- u64 time;
-
- if (!in_nmi()) {
- update_context_time(counter->ctx);
- time = counter->ctx->time;
- } else {
- u64 now = perf_clock();
- u64 delta = now - counter->ctx->timestamp;
- time = counter->ctx->time + delta;
- }
-
- task_clock_perf_counter_update(counter, time);
-}
-
-static const struct pmu perf_ops_task_clock = {
- .enable = task_clock_perf_counter_enable,
- .disable = task_clock_perf_counter_disable,
- .read = task_clock_perf_counter_read,
-};
-
-#ifdef CONFIG_EVENT_PROFILE
-void perf_tpcounter_event(int event_id, u64 addr, u64 count, void *record,
- int entry_size)
-{
- struct perf_raw_record raw = {
- .size = entry_size,
- .data = record,
- };
-
- struct perf_sample_data data = {
- .regs = get_irq_regs(),
- .addr = addr,
- .raw = &raw,
- };
-
- if (!data.regs)
- data.regs = task_pt_regs(current);
-
- do_perf_swcounter_event(PERF_TYPE_TRACEPOINT, event_id, count, 1, &data);
-}
-EXPORT_SYMBOL_GPL(perf_tpcounter_event);
-
-extern int ftrace_profile_enable(int);
-extern void ftrace_profile_disable(int);
-
-static void tp_perf_counter_destroy(struct perf_counter *counter)
-{
- ftrace_profile_disable(counter->attr.config);
-}
-
-static const struct pmu *tp_perf_counter_init(struct perf_counter *counter)
-{
- /*
- * Raw tracepoint data is a severe data leak, only allow root to
- * have these.
- */
- if ((counter->attr.sample_type & PERF_SAMPLE_RAW) &&
- perf_paranoid_tracepoint_raw() &&
- !capable(CAP_SYS_ADMIN))
- return ERR_PTR(-EPERM);
-
- if (ftrace_profile_enable(counter->attr.config))
- return NULL;
-
- counter->destroy = tp_perf_counter_destroy;
-
- return &perf_ops_generic;
-}
-#else
-static const struct pmu *tp_perf_counter_init(struct perf_counter *counter)
-{
- return NULL;
-}
-#endif
-
-atomic_t perf_swcounter_enabled[PERF_COUNT_SW_MAX];
-
-static void sw_perf_counter_destroy(struct perf_counter *counter)
-{
- u64 event = counter->attr.config;
-
- WARN_ON(counter->parent);
-
- atomic_dec(&perf_swcounter_enabled[event]);
-}
-
-static const struct pmu *sw_perf_counter_init(struct perf_counter *counter)
-{
- const struct pmu *pmu = NULL;
- u64 event = counter->attr.config;
-
- /*
- * Software counters (currently) can't in general distinguish
- * between user, kernel and hypervisor events.
- * However, context switches and cpu migrations are considered
- * to be kernel events, and page faults are never hypervisor
- * events.
- */
- switch (event) {
- case PERF_COUNT_SW_CPU_CLOCK:
- pmu = &perf_ops_cpu_clock;
-
- break;
- case PERF_COUNT_SW_TASK_CLOCK:
- /*
- * If the user instantiates this as a per-cpu counter,
- * use the cpu_clock counter instead.
- */
- if (counter->ctx->task)
- pmu = &perf_ops_task_clock;
- else
- pmu = &perf_ops_cpu_clock;
-
- break;
- case PERF_COUNT_SW_PAGE_FAULTS:
- case PERF_COUNT_SW_PAGE_FAULTS_MIN:
- case PERF_COUNT_SW_PAGE_FAULTS_MAJ:
- case PERF_COUNT_SW_CONTEXT_SWITCHES:
- case PERF_COUNT_SW_CPU_MIGRATIONS:
- if (!counter->parent) {
- atomic_inc(&perf_swcounter_enabled[event]);
- counter->destroy = sw_perf_counter_destroy;
- }
- pmu = &perf_ops_generic;
- break;
- }
-
- return pmu;
-}
-
-/*
- * Allocate and initialize a counter structure
- */
-static struct perf_counter *
-perf_counter_alloc(struct perf_counter_attr *attr,
- int cpu,
- struct perf_counter_context *ctx,
- struct perf_counter *group_leader,
- struct perf_counter *parent_counter,
- gfp_t gfpflags)
-{
- const struct pmu *pmu;
- struct perf_counter *counter;
- struct hw_perf_counter *hwc;
- long err;
-
- counter = kzalloc(sizeof(*counter), gfpflags);
- if (!counter)
- return ERR_PTR(-ENOMEM);
-
- /*
- * Single counters are their own group leaders, with an
- * empty sibling list:
- */
- if (!group_leader)
- group_leader = counter;
-
- mutex_init(&counter->child_mutex);
- INIT_LIST_HEAD(&counter->child_list);
-
- INIT_LIST_HEAD(&counter->list_entry);
- INIT_LIST_HEAD(&counter->event_entry);
- INIT_LIST_HEAD(&counter->sibling_list);
- init_waitqueue_head(&counter->waitq);
-
- mutex_init(&counter->mmap_mutex);
-
- counter->cpu = cpu;
- counter->attr = *attr;
- counter->group_leader = group_leader;
- counter->pmu = NULL;
- counter->ctx = ctx;
- counter->oncpu = -1;
-
- counter->parent = parent_counter;
-
- counter->ns = get_pid_ns(current->nsproxy->pid_ns);
- counter->id = atomic64_inc_return(&perf_counter_id);
-
- counter->state = PERF_COUNTER_STATE_INACTIVE;
-
- if (attr->disabled)
- counter->state = PERF_COUNTER_STATE_OFF;
-
- pmu = NULL;
-
- hwc = &counter->hw;
- hwc->sample_period = attr->sample_period;
- if (attr->freq && attr->sample_freq)
- hwc->sample_period = 1;
- hwc->last_period = hwc->sample_period;
-
- atomic64_set(&hwc->period_left, hwc->sample_period);
-
- /*
- * we currently do not support PERF_FORMAT_GROUP on inherited counters
- */
- if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP))
- goto done;
-
- switch (attr->type) {
- case PERF_TYPE_RAW:
- case PERF_TYPE_HARDWARE:
- case PERF_TYPE_HW_CACHE:
- pmu = hw_perf_counter_init(counter);
- break;
-
- case PERF_TYPE_SOFTWARE:
- pmu = sw_perf_counter_init(counter);
- break;
-
- case PERF_TYPE_TRACEPOINT:
- pmu = tp_perf_counter_init(counter);
- break;
-
- default:
- break;
- }
-done:
- err = 0;
- if (!pmu)
- err = -EINVAL;
- else if (IS_ERR(pmu))
- err = PTR_ERR(pmu);
-
- if (err) {
- if (counter->ns)
- put_pid_ns(counter->ns);
- kfree(counter);
- return ERR_PTR(err);
- }
-
- counter->pmu = pmu;
-
- if (!counter->parent) {
- atomic_inc(&nr_counters);
- if (counter->attr.mmap)
- atomic_inc(&nr_mmap_counters);
- if (counter->attr.comm)
- atomic_inc(&nr_comm_counters);
- if (counter->attr.task)
- atomic_inc(&nr_task_counters);
- }
-
- return counter;
-}
-
-static int perf_copy_attr(struct perf_counter_attr __user *uattr,
- struct perf_counter_attr *attr)
-{
- int ret;
- u32 size;
-
- if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0))
- return -EFAULT;
-
- /*
- * zero the full structure, so that a short copy will be nice.
- */
- memset(attr, 0, sizeof(*attr));
-
- ret = get_user(size, &uattr->size);
- if (ret)
- return ret;
-
- if (size > PAGE_SIZE) /* silly large */
- goto err_size;
-
- if (!size) /* abi compat */
- size = PERF_ATTR_SIZE_VER0;
-
- if (size < PERF_ATTR_SIZE_VER0)
- goto err_size;
-
- /*
- * If we're handed a bigger struct than we know of,
- * ensure all the unknown bits are 0.
- */
- if (size > sizeof(*attr)) {
- unsigned long val;
- unsigned long __user *addr;
- unsigned long __user *end;
-
- addr = PTR_ALIGN((void __user *)uattr + sizeof(*attr),
- sizeof(unsigned long));
- end = PTR_ALIGN((void __user *)uattr + size,
- sizeof(unsigned long));
-
- for (; addr < end; addr += sizeof(unsigned long)) {
- ret = get_user(val, addr);
- if (ret)
- return ret;
- if (val)
- goto err_size;
- }
- size = sizeof(*attr);
- }
-
- ret = copy_from_user(attr, uattr, size);
- if (ret)
- return -EFAULT;
-
- /*
- * If the type exists, the corresponding creation will verify
- * the attr->config.
- */
- if (attr->type >= PERF_TYPE_MAX)
- return -EINVAL;
-
- if (attr->__reserved_1 || attr->__reserved_2 || attr->__reserved_3)
- return -EINVAL;
-
- if (attr->sample_type & ~(PERF_SAMPLE_MAX-1))
- return -EINVAL;
-
- if (attr->read_format & ~(PERF_FORMAT_MAX-1))
- return -EINVAL;
-
-out:
- return ret;
-
-err_size:
- put_user(sizeof(*attr), &uattr->size);
- ret = -E2BIG;
- goto out;
-}
-
-int perf_counter_set_output(struct perf_counter *counter, int output_fd)
-{
- struct perf_counter *output_counter = NULL;
- struct file *output_file = NULL;
- struct perf_counter *old_output;
- int fput_needed = 0;
- int ret = -EINVAL;
-
- if (!output_fd)
- goto set;
-
- output_file = fget_light(output_fd, &fput_needed);
- if (!output_file)
- return -EBADF;
-
- if (output_file->f_op != &perf_fops)
- goto out;
-
- output_counter = output_file->private_data;
-
- /* Don't chain output fds */
- if (output_counter->output)
- goto out;
-
- /* Don't set an output fd when we already have an output channel */
- if (counter->data)
- goto out;
-
- atomic_long_inc(&output_file->f_count);
-
-set:
- mutex_lock(&counter->mmap_mutex);
- old_output = counter->output;
- rcu_assign_pointer(counter->output, output_counter);
- mutex_unlock(&counter->mmap_mutex);
-
- if (old_output) {
- /*
- * we need to make sure no existing perf_output_*()
- * is still referencing this counter.
- */
- synchronize_rcu();
- fput(old_output->filp);
- }
-
- ret = 0;
-out:
- fput_light(output_file, fput_needed);
- return ret;
-}
-
-/**
- * sys_perf_counter_open - open a performance counter, associate it to a task/cpu
- *
- * @attr_uptr: event type attributes for monitoring/sampling
- * @pid: target pid
- * @cpu: target cpu
- * @group_fd: group leader counter fd
- */
-SYSCALL_DEFINE5(perf_counter_open,
- struct perf_counter_attr __user *, attr_uptr,
- pid_t, pid, int, cpu, int, group_fd, unsigned long, flags)
-{
- struct perf_counter *counter, *group_leader;
- struct perf_counter_attr attr;
- struct perf_counter_context *ctx;
- struct file *counter_file = NULL;
- struct file *group_file = NULL;
- int fput_needed = 0;
- int fput_needed2 = 0;
- int err;
-
- /* for future expandability... */
- if (flags & ~(PERF_FLAG_FD_NO_GROUP | PERF_FLAG_FD_OUTPUT))
- return -EINVAL;
-
- err = perf_copy_attr(attr_uptr, &attr);
- if (err)
- return err;
-
- if (!attr.exclude_kernel) {
- if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN))
- return -EACCES;
- }
-
- if (attr.freq) {
- if (attr.sample_freq > sysctl_perf_counter_sample_rate)
- return -EINVAL;
- }
-
- /*
- * Get the target context (task or percpu):
- */
- ctx = find_get_context(pid, cpu);
- if (IS_ERR(ctx))
- return PTR_ERR(ctx);
-
- /*
- * Look up the group leader (we will attach this counter to it):
- */
- group_leader = NULL;
- if (group_fd != -1 && !(flags & PERF_FLAG_FD_NO_GROUP)) {
- err = -EINVAL;
- group_file = fget_light(group_fd, &fput_needed);
- if (!group_file)
- goto err_put_context;
- if (group_file->f_op != &perf_fops)
- goto err_put_context;
-
- group_leader = group_file->private_data;
- /*
- * Do not allow a recursive hierarchy (this new sibling
- * becoming part of another group-sibling):
- */
- if (group_leader->group_leader != group_leader)
- goto err_put_context;
- /*
- * Do not allow to attach to a group in a different
- * task or CPU context:
- */
- if (group_leader->ctx != ctx)
- goto err_put_context;
- /*
- * Only a group leader can be exclusive or pinned
- */
- if (attr.exclusive || attr.pinned)
- goto err_put_context;
- }
-
- counter = perf_counter_alloc(&attr, cpu, ctx, group_leader,
- NULL, GFP_KERNEL);
- err = PTR_ERR(counter);
- if (IS_ERR(counter))
- goto err_put_context;
-
- err = anon_inode_getfd("[perf_counter]", &perf_fops, counter, 0);
- if (err < 0)
- goto err_free_put_context;
-
- counter_file = fget_light(err, &fput_needed2);
- if (!counter_file)
- goto err_free_put_context;
-
- if (flags & PERF_FLAG_FD_OUTPUT) {
- err = perf_counter_set_output(counter, group_fd);
- if (err)
- goto err_fput_free_put_context;
- }
-
- counter->filp = counter_file;
- WARN_ON_ONCE(ctx->parent_ctx);
- mutex_lock(&ctx->mutex);
- perf_install_in_context(ctx, counter, cpu);
- ++ctx->generation;
- mutex_unlock(&ctx->mutex);
-
- counter->owner = current;
- get_task_struct(current);
- mutex_lock(&current->perf_counter_mutex);
- list_add_tail(&counter->owner_entry, &current->perf_counter_list);
- mutex_unlock(&current->perf_counter_mutex);
-
-err_fput_free_put_context:
- fput_light(counter_file, fput_needed2);
-
-err_free_put_context:
- if (err < 0)
- kfree(counter);
-
-err_put_context:
- if (err < 0)
- put_ctx(ctx);
-
- fput_light(group_file, fput_needed);
-
- return err;
-}
-
-/*
- * inherit a counter from parent task to child task:
- */
-static struct perf_counter *
-inherit_counter(struct perf_counter *parent_counter,
- struct task_struct *parent,
- struct perf_counter_context *parent_ctx,
- struct task_struct *child,
- struct perf_counter *group_leader,
- struct perf_counter_context *child_ctx)
-{
- struct perf_counter *child_counter;
-
- /*
- * Instead of creating recursive hierarchies of counters,
- * we link inherited counters back to the original parent,
- * which has a filp for sure, which we use as the reference
- * count:
- */
- if (parent_counter->parent)
- parent_counter = parent_counter->parent;
-
- child_counter = perf_counter_alloc(&parent_counter->attr,
- parent_counter->cpu, child_ctx,
- group_leader, parent_counter,
- GFP_KERNEL);
- if (IS_ERR(child_counter))
- return child_counter;
- get_ctx(child_ctx);
-
- /*
- * Make the child state follow the state of the parent counter,
- * not its attr.disabled bit. We hold the parent's mutex,
- * so we won't race with perf_counter_{en, dis}able_family.
- */
- if (parent_counter->state >= PERF_COUNTER_STATE_INACTIVE)
- child_counter->state = PERF_COUNTER_STATE_INACTIVE;
- else
- child_counter->state = PERF_COUNTER_STATE_OFF;
-
- if (parent_counter->attr.freq)
- child_counter->hw.sample_period = parent_counter->hw.sample_period;
-
- /*
- * Link it up in the child's context:
- */
- add_counter_to_ctx(child_counter, child_ctx);
-
- /*
- * Get a reference to the parent filp - we will fput it
- * when the child counter exits. This is safe to do because
- * we are in the parent and we know that the filp still
- * exists and has a nonzero count:
- */
- atomic_long_inc(&parent_counter->filp->f_count);
-
- /*
- * Link this into the parent counter's child list
- */
- WARN_ON_ONCE(parent_counter->ctx->parent_ctx);
- mutex_lock(&parent_counter->child_mutex);
- list_add_tail(&child_counter->child_list, &parent_counter->child_list);
- mutex_unlock(&parent_counter->child_mutex);
-
- return child_counter;
-}
-
-static int inherit_group(struct perf_counter *parent_counter,
- struct task_struct *parent,
- struct perf_counter_context *parent_ctx,
- struct task_struct *child,
- struct perf_counter_context *child_ctx)
-{
- struct perf_counter *leader;
- struct perf_counter *sub;
- struct perf_counter *child_ctr;
-
- leader = inherit_counter(parent_counter, parent, parent_ctx,
- child, NULL, child_ctx);
- if (IS_ERR(leader))
- return PTR_ERR(leader);
- list_for_each_entry(sub, &parent_counter->sibling_list, list_entry) {
- child_ctr = inherit_counter(sub, parent, parent_ctx,
- child, leader, child_ctx);
- if (IS_ERR(child_ctr))
- return PTR_ERR(child_ctr);
- }
- return 0;
-}
-
-static void sync_child_counter(struct perf_counter *child_counter,
- struct task_struct *child)
-{
- struct perf_counter *parent_counter = child_counter->parent;
- u64 child_val;
-
- if (child_counter->attr.inherit_stat)
- perf_counter_read_event(child_counter, child);
-
- child_val = atomic64_read(&child_counter->count);
-
- /*
- * Add back the child's count to the parent's count:
- */
- atomic64_add(child_val, &parent_counter->count);
- atomic64_add(child_counter->total_time_enabled,
- &parent_counter->child_total_time_enabled);
- atomic64_add(child_counter->total_time_running,
- &parent_counter->child_total_time_running);
-
- /*
- * Remove this counter from the parent's list
- */
- WARN_ON_ONCE(parent_counter->ctx->parent_ctx);
- mutex_lock(&parent_counter->child_mutex);
- list_del_init(&child_counter->child_list);
- mutex_unlock(&parent_counter->child_mutex);
-
- /*
- * Release the parent counter, if this was the last
- * reference to it.
- */
- fput(parent_counter->filp);
-}
-
-static void
-__perf_counter_exit_task(struct perf_counter *child_counter,
- struct perf_counter_context *child_ctx,
- struct task_struct *child)
-{
- struct perf_counter *parent_counter;
-
- update_counter_times(child_counter);
- perf_counter_remove_from_context(child_counter);
-
- parent_counter = child_counter->parent;
- /*
- * It can happen that parent exits first, and has counters
- * that are still around due to the child reference. These
- * counters need to be zapped - but otherwise linger.
- */
- if (parent_counter) {
- sync_child_counter(child_counter, child);
- free_counter(child_counter);
- }
-}
-
-/*
- * When a child task exits, feed back counter values to parent counters.
- */
-void perf_counter_exit_task(struct task_struct *child)
-{
- struct perf_counter *child_counter, *tmp;
- struct perf_counter_context *child_ctx;
- unsigned long flags;
-
- if (likely(!child->perf_counter_ctxp)) {
- perf_counter_task(child, NULL, 0);
- return;
- }
-
- local_irq_save(flags);
- /*
- * We can't reschedule here because interrupts are disabled,
- * and either child is current or it is a task that can't be
- * scheduled, so we are now safe from rescheduling changing
- * our context.
- */
- child_ctx = child->perf_counter_ctxp;
- __perf_counter_task_sched_out(child_ctx);
-
- /*
- * Take the context lock here so that if find_get_context is
- * reading child->perf_counter_ctxp, we wait until it has
- * incremented the context's refcount before we do put_ctx below.
- */
- spin_lock(&child_ctx->lock);
- child->perf_counter_ctxp = NULL;
- /*
- * If this context is a clone; unclone it so it can't get
- * swapped to another process while we're removing all
- * the counters from it.
- */
- unclone_ctx(child_ctx);
- spin_unlock_irqrestore(&child_ctx->lock, flags);
-
- /*
- * Report the task dead after unscheduling the counters so that we
- * won't get any samples after PERF_EVENT_EXIT. We can however still
- * get a few PERF_EVENT_READ events.
- */
- perf_counter_task(child, child_ctx, 0);
-
- /*
- * We can recurse on the same lock type through:
- *
- * __perf_counter_exit_task()
- * sync_child_counter()
- * fput(parent_counter->filp)
- * perf_release()
- * mutex_lock(&ctx->mutex)
- *
- * But since its the parent context it won't be the same instance.
- */
- mutex_lock_nested(&child_ctx->mutex, SINGLE_DEPTH_NESTING);
-
-again:
- list_for_each_entry_safe(child_counter, tmp, &child_ctx->counter_list,
- list_entry)
- __perf_counter_exit_task(child_counter, child_ctx, child);
-
- /*
- * If the last counter was a group counter, it will have appended all
- * its siblings to the list, but we obtained 'tmp' before that which
- * will still point to the list head terminating the iteration.
- */
- if (!list_empty(&child_ctx->counter_list))
- goto again;
-
- mutex_unlock(&child_ctx->mutex);
-
- put_ctx(child_ctx);
-}
-
-/*
- * free an unexposed, unused context as created by inheritance by
- * init_task below, used by fork() in case of fail.
- */
-void perf_counter_free_task(struct task_struct *task)
-{
- struct perf_counter_context *ctx = task->perf_counter_ctxp;
- struct perf_counter *counter, *tmp;
-
- if (!ctx)
- return;
-
- mutex_lock(&ctx->mutex);
-again:
- list_for_each_entry_safe(counter, tmp, &ctx->counter_list, list_entry) {
- struct perf_counter *parent = counter->parent;
-
- if (WARN_ON_ONCE(!parent))
- continue;
-
- mutex_lock(&parent->child_mutex);
- list_del_init(&counter->child_list);
- mutex_unlock(&parent->child_mutex);
-
- fput(parent->filp);
-
- list_del_counter(counter, ctx);
- free_counter(counter);
- }
-
- if (!list_empty(&ctx->counter_list))
- goto again;
-
- mutex_unlock(&ctx->mutex);
-
- put_ctx(ctx);
-}
-
-/*
- * Initialize the perf_counter context in task_struct
- */
-int perf_counter_init_task(struct task_struct *child)
-{
- struct perf_counter_context *child_ctx, *parent_ctx;
- struct perf_counter_context *cloned_ctx;
- struct perf_counter *counter;
- struct task_struct *parent = current;
- int inherited_all = 1;
- int ret = 0;
-
- child->perf_counter_ctxp = NULL;
-
- mutex_init(&child->perf_counter_mutex);
- INIT_LIST_HEAD(&child->perf_counter_list);
-
- if (likely(!parent->perf_counter_ctxp))
- return 0;
-
- /*
- * This is executed from the parent task context, so inherit
- * counters that have been marked for cloning.
- * First allocate and initialize a context for the child.
- */
-
- child_ctx = kmalloc(sizeof(struct perf_counter_context), GFP_KERNEL);
- if (!child_ctx)
- return -ENOMEM;
-
- __perf_counter_init_context(child_ctx, child);
- child->perf_counter_ctxp = child_ctx;
- get_task_struct(child);
-
- /*
- * If the parent's context is a clone, pin it so it won't get
- * swapped under us.
- */
- parent_ctx = perf_pin_task_context(parent);
-
- /*
- * No need to check if parent_ctx != NULL here; since we saw
- * it non-NULL earlier, the only reason for it to become NULL
- * is if we exit, and since we're currently in the middle of
- * a fork we can't be exiting at the same time.
- */
-
- /*
- * Lock the parent list. No need to lock the child - not PID
- * hashed yet and not running, so nobody can access it.
- */
- mutex_lock(&parent_ctx->mutex);
-
- /*
- * We dont have to disable NMIs - we are only looking at
- * the list, not manipulating it:
- */
- list_for_each_entry_rcu(counter, &parent_ctx->event_list, event_entry) {
- if (counter != counter->group_leader)
- continue;
-
- if (!counter->attr.inherit) {
- inherited_all = 0;
- continue;
- }
-
- ret = inherit_group(counter, parent, parent_ctx,
- child, child_ctx);
- if (ret) {
- inherited_all = 0;
- break;
- }
- }
-
- if (inherited_all) {
- /*
- * Mark the child context as a clone of the parent
- * context, or of whatever the parent is a clone of.
- * Note that if the parent is a clone, it could get
- * uncloned at any point, but that doesn't matter
- * because the list of counters and the generation
- * count can't have changed since we took the mutex.
- */
- cloned_ctx = rcu_dereference(parent_ctx->parent_ctx);
- if (cloned_ctx) {
- child_ctx->parent_ctx = cloned_ctx;
- child_ctx->parent_gen = parent_ctx->parent_gen;
- } else {
- child_ctx->parent_ctx = parent_ctx;
- child_ctx->parent_gen = parent_ctx->generation;
- }
- get_ctx(child_ctx->parent_ctx);
- }
-
- mutex_unlock(&parent_ctx->mutex);
-
- perf_unpin_context(parent_ctx);
-
- return ret;
-}
-
-static void __cpuinit perf_counter_init_cpu(int cpu)
-{
- struct perf_cpu_context *cpuctx;
-
- cpuctx = &per_cpu(perf_cpu_context, cpu);
- __perf_counter_init_context(&cpuctx->ctx, NULL);
-
- spin_lock(&perf_resource_lock);
- cpuctx->max_pertask = perf_max_counters - perf_reserved_percpu;
- spin_unlock(&perf_resource_lock);
-
- hw_perf_counter_setup(cpu);
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-static void __perf_counter_exit_cpu(void *info)
-{
- struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
- struct perf_counter_context *ctx = &cpuctx->ctx;
- struct perf_counter *counter, *tmp;
-
- list_for_each_entry_safe(counter, tmp, &ctx->counter_list, list_entry)
- __perf_counter_remove_from_context(counter);
-}
-static void perf_counter_exit_cpu(int cpu)
-{
- struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
- struct perf_counter_context *ctx = &cpuctx->ctx;
-
- mutex_lock(&ctx->mutex);
- smp_call_function_single(cpu, __perf_counter_exit_cpu, NULL, 1);
- mutex_unlock(&ctx->mutex);
-}
-#else
-static inline void perf_counter_exit_cpu(int cpu) { }
-#endif
-
-static int __cpuinit
-perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu)
-{
- unsigned int cpu = (long)hcpu;
-
- switch (action) {
-
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
- perf_counter_init_cpu(cpu);
- break;
-
- case CPU_ONLINE:
- case CPU_ONLINE_FROZEN:
- hw_perf_counter_setup_online(cpu);
- break;
-
- case CPU_DOWN_PREPARE:
- case CPU_DOWN_PREPARE_FROZEN:
- perf_counter_exit_cpu(cpu);
- break;
-
- default:
- break;
- }
-
- return NOTIFY_OK;
-}
-
-/*
- * This has to have a higher priority than migration_notifier in sched.c.
- */
-static struct notifier_block __cpuinitdata perf_cpu_nb = {
- .notifier_call = perf_cpu_notify,
- .priority = 20,
-};
-
-void __init perf_counter_init(void)
-{
- perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_UP_PREPARE,
- (void *)(long)smp_processor_id());
- perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_ONLINE,
- (void *)(long)smp_processor_id());
- register_cpu_notifier(&perf_cpu_nb);
-}
-
-static ssize_t perf_show_reserve_percpu(struct sysdev_class *class, char *buf)
-{
- return sprintf(buf, "%d\n", perf_reserved_percpu);
-}
-
-static ssize_t
-perf_set_reserve_percpu(struct sysdev_class *class,
- const char *buf,
- size_t count)
-{
- struct perf_cpu_context *cpuctx;
- unsigned long val;
- int err, cpu, mpt;
-
- err = strict_strtoul(buf, 10, &val);
- if (err)
- return err;
- if (val > perf_max_counters)
- return -EINVAL;
-
- spin_lock(&perf_resource_lock);
- perf_reserved_percpu = val;
- for_each_online_cpu(cpu) {
- cpuctx = &per_cpu(perf_cpu_context, cpu);
- spin_lock_irq(&cpuctx->ctx.lock);
- mpt = min(perf_max_counters - cpuctx->ctx.nr_counters,
- perf_max_counters - perf_reserved_percpu);
- cpuctx->max_pertask = mpt;
- spin_unlock_irq(&cpuctx->ctx.lock);
- }
- spin_unlock(&perf_resource_lock);
-
- return count;
-}
-
-static ssize_t perf_show_overcommit(struct sysdev_class *class, char *buf)
-{
- return sprintf(buf, "%d\n", perf_overcommit);
-}
-
-static ssize_t
-perf_set_overcommit(struct sysdev_class *class, const char *buf, size_t count)
-{
- unsigned long val;
- int err;
-
- err = strict_strtoul(buf, 10, &val);
- if (err)
- return err;
- if (val > 1)
- return -EINVAL;
-
- spin_lock(&perf_resource_lock);
- perf_overcommit = val;
- spin_unlock(&perf_resource_lock);
-
- return count;
-}
-
-static SYSDEV_CLASS_ATTR(
- reserve_percpu,
- 0644,
- perf_show_reserve_percpu,
- perf_set_reserve_percpu
- );
-
-static SYSDEV_CLASS_ATTR(
- overcommit,
- 0644,
- perf_show_overcommit,
- perf_set_overcommit
- );
-
-static struct attribute *perfclass_attrs[] = {
- &attr_reserve_percpu.attr,
- &attr_overcommit.attr,
- NULL
-};
-
-static struct attribute_group perfclass_attr_group = {
- .attrs = perfclass_attrs,
- .name = "perf_counters",
-};
-
-static int __init perf_counter_sysfs_init(void)
-{
- return sysfs_create_group(&cpu_sysdev_class.kset.kobj,
- &perfclass_attr_group);
-}
-device_initcall(perf_counter_sysfs_init);
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
new file mode 100644
index 00000000000..0f86feb6db0
--- /dev/null
+++ b/kernel/perf_event.c
@@ -0,0 +1,5000 @@
+/*
+ * Performance events core code:
+ *
+ * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
+ * Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar
+ * Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
+ *
+ * For licensing details see kernel-base/COPYING
+ */
+
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/cpu.h>
+#include <linux/smp.h>
+#include <linux/file.h>
+#include <linux/poll.h>
+#include <linux/sysfs.h>
+#include <linux/dcache.h>
+#include <linux/percpu.h>
+#include <linux/ptrace.h>
+#include <linux/vmstat.h>
+#include <linux/hardirq.h>
+#include <linux/rculist.h>
+#include <linux/uaccess.h>
+#include <linux/syscalls.h>
+#include <linux/anon_inodes.h>
+#include <linux/kernel_stat.h>
+#include <linux/perf_event.h>
+
+#include <asm/irq_regs.h>
+
+/*
+ * Each CPU has a list of per CPU events:
+ */
+DEFINE_PER_CPU(struct perf_cpu_context, perf_cpu_context);
+
+int perf_max_events __read_mostly = 1;
+static int perf_reserved_percpu __read_mostly;
+static int perf_overcommit __read_mostly = 1;
+
+static atomic_t nr_events __read_mostly;
+static atomic_t nr_mmap_events __read_mostly;
+static atomic_t nr_comm_events __read_mostly;
+static atomic_t nr_task_events __read_mostly;
+
+/*
+ * perf event paranoia level:
+ * -1 - not paranoid at all
+ * 0 - disallow raw tracepoint access for unpriv
+ * 1 - disallow cpu events for unpriv
+ * 2 - disallow kernel profiling for unpriv
+ */
+int sysctl_perf_event_paranoid __read_mostly = 1;
+
+static inline bool perf_paranoid_tracepoint_raw(void)
+{
+ return sysctl_perf_event_paranoid > -1;
+}
+
+static inline bool perf_paranoid_cpu(void)
+{
+ return sysctl_perf_event_paranoid > 0;
+}
+
+static inline bool perf_paranoid_kernel(void)
+{
+ return sysctl_perf_event_paranoid > 1;
+}
+
+int sysctl_perf_event_mlock __read_mostly = 512; /* 'free' kb per user */
+
+/*
+ * max perf event sample rate
+ */
+int sysctl_perf_event_sample_rate __read_mostly = 100000;
+
+static atomic64_t perf_event_id;
+
+/*
+ * Lock for (sysadmin-configurable) event reservations:
+ */
+static DEFINE_SPINLOCK(perf_resource_lock);
+
+/*
+ * Architecture provided APIs - weak aliases:
+ */
+extern __weak const struct pmu *hw_perf_event_init(struct perf_event *event)
+{
+ return NULL;
+}
+
+void __weak hw_perf_disable(void) { barrier(); }
+void __weak hw_perf_enable(void) { barrier(); }
+
+void __weak hw_perf_event_setup(int cpu) { barrier(); }
+void __weak hw_perf_event_setup_online(int cpu) { barrier(); }
+
+int __weak
+hw_perf_group_sched_in(struct perf_event *group_leader,
+ struct perf_cpu_context *cpuctx,
+ struct perf_event_context *ctx, int cpu)
+{
+ return 0;
+}
+
+void __weak perf_event_print_debug(void) { }
+
+static DEFINE_PER_CPU(int, perf_disable_count);
+
+void __perf_disable(void)
+{
+ __get_cpu_var(perf_disable_count)++;
+}
+
+bool __perf_enable(void)
+{
+ return !--__get_cpu_var(perf_disable_count);
+}
+
+void perf_disable(void)
+{
+ __perf_disable();
+ hw_perf_disable();
+}
+
+void perf_enable(void)
+{
+ if (__perf_enable())
+ hw_perf_enable();
+}
+
+static void get_ctx(struct perf_event_context *ctx)
+{
+ WARN_ON(!atomic_inc_not_zero(&ctx->refcount));
+}
+
+static void free_ctx(struct rcu_head *head)
+{
+ struct perf_event_context *ctx;
+
+ ctx = container_of(head, struct perf_event_context, rcu_head);
+ kfree(ctx);
+}
+
+static void put_ctx(struct perf_event_context *ctx)
+{
+ if (atomic_dec_and_test(&ctx->refcount)) {
+ if (ctx->parent_ctx)
+ put_ctx(ctx->parent_ctx);
+ if (ctx->task)
+ put_task_struct(ctx->task);
+ call_rcu(&ctx->rcu_head, free_ctx);
+ }
+}
+
+static void unclone_ctx(struct perf_event_context *ctx)
+{
+ if (ctx->parent_ctx) {
+ put_ctx(ctx->parent_ctx);
+ ctx->parent_ctx = NULL;
+ }
+}
+
+/*
+ * If we inherit events we want to return the parent event id
+ * to userspace.
+ */
+static u64 primary_event_id(struct perf_event *event)
+{
+ u64 id = event->id;
+
+ if (event->parent)
+ id = event->parent->id;
+
+ return id;
+}
+
+/*
+ * Get the perf_event_context for a task and lock it.
+ * This has to cope with with the fact that until it is locked,
+ * the context could get moved to another task.
+ */
+static struct perf_event_context *
+perf_lock_task_context(struct task_struct *task, unsigned long *flags)
+{
+ struct perf_event_context *ctx;
+
+ rcu_read_lock();
+ retry:
+ ctx = rcu_dereference(task->perf_event_ctxp);
+ if (ctx) {
+ /*
+ * If this context is a clone of another, it might
+ * get swapped for another underneath us by
+ * perf_event_task_sched_out, though the
+ * rcu_read_lock() protects us from any context
+ * getting freed. Lock the context and check if it
+ * got swapped before we could get the lock, and retry
+ * if so. If we locked the right context, then it
+ * can't get swapped on us any more.
+ */
+ spin_lock_irqsave(&ctx->lock, *flags);
+ if (ctx != rcu_dereference(task->perf_event_ctxp)) {
+ spin_unlock_irqrestore(&ctx->lock, *flags);
+ goto retry;
+ }
+
+ if (!atomic_inc_not_zero(&ctx->refcount)) {
+ spin_unlock_irqrestore(&ctx->lock, *flags);
+ ctx = NULL;
+ }
+ }
+ rcu_read_unlock();
+ return ctx;
+}
+
+/*
+ * Get the context for a task and increment its pin_count so it
+ * can't get swapped to another task. This also increments its
+ * reference count so that the context can't get freed.
+ */
+static struct perf_event_context *perf_pin_task_context(struct task_struct *task)
+{
+ struct perf_event_context *ctx;
+ unsigned long flags;
+
+ ctx = perf_lock_task_context(task, &flags);
+ if (ctx) {
+ ++ctx->pin_count;
+ spin_unlock_irqrestore(&ctx->lock, flags);
+ }
+ return ctx;
+}
+
+static void perf_unpin_context(struct perf_event_context *ctx)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&ctx->lock, flags);
+ --ctx->pin_count;
+ spin_unlock_irqrestore(&ctx->lock, flags);
+ put_ctx(ctx);
+}
+
+/*
+ * Add a event from the lists for its context.
+ * Must be called with ctx->mutex and ctx->lock held.
+ */
+static void
+list_add_event(struct perf_event *event, struct perf_event_context *ctx)
+{
+ struct perf_event *group_leader = event->group_leader;
+
+ /*
+ * Depending on whether it is a standalone or sibling event,
+ * add it straight to the context's event list, or to the group
+ * leader's sibling list:
+ */
+ if (group_leader == event)
+ list_add_tail(&event->group_entry, &ctx->group_list);
+ else {
+ list_add_tail(&event->group_entry, &group_leader->sibling_list);
+ group_leader->nr_siblings++;
+ }
+
+ list_add_rcu(&event->event_entry, &ctx->event_list);
+ ctx->nr_events++;
+ if (event->attr.inherit_stat)
+ ctx->nr_stat++;
+}
+
+/*
+ * Remove a event from the lists for its context.
+ * Must be called with ctx->mutex and ctx->lock held.
+ */
+static void
+list_del_event(struct perf_event *event, struct perf_event_context *ctx)
+{
+ struct perf_event *sibling, *tmp;
+
+ if (list_empty(&event->group_entry))
+ return;
+ ctx->nr_events--;
+ if (event->attr.inherit_stat)
+ ctx->nr_stat--;
+
+ list_del_init(&event->group_entry);
+ list_del_rcu(&event->event_entry);
+
+ if (event->group_leader != event)
+ event->group_leader->nr_siblings--;
+
+ /*
+ * If this was a group event with sibling events then
+ * upgrade the siblings to singleton events by adding them
+ * to the context list directly:
+ */
+ list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) {
+
+ list_move_tail(&sibling->group_entry, &ctx->group_list);
+ sibling->group_leader = sibling;
+ }
+}
+
+static void
+event_sched_out(struct perf_event *event,
+ struct perf_cpu_context *cpuctx,
+ struct perf_event_context *ctx)
+{
+ if (event->state != PERF_EVENT_STATE_ACTIVE)
+ return;
+
+ event->state = PERF_EVENT_STATE_INACTIVE;
+ if (event->pending_disable) {
+ event->pending_disable = 0;
+ event->state = PERF_EVENT_STATE_OFF;
+ }
+ event->tstamp_stopped = ctx->time;
+ event->pmu->disable(event);
+ event->oncpu = -1;
+
+ if (!is_software_event(event))
+ cpuctx->active_oncpu--;
+ ctx->nr_active--;
+ if (event->attr.exclusive || !cpuctx->active_oncpu)
+ cpuctx->exclusive = 0;
+}
+
+static void
+group_sched_out(struct perf_event *group_event,
+ struct perf_cpu_context *cpuctx,
+ struct perf_event_context *ctx)
+{
+ struct perf_event *event;
+
+ if (group_event->state != PERF_EVENT_STATE_ACTIVE)
+ return;
+
+ event_sched_out(group_event, cpuctx, ctx);
+
+ /*
+ * Schedule out siblings (if any):
+ */
+ list_for_each_entry(event, &group_event->sibling_list, group_entry)
+ event_sched_out(event, cpuctx, ctx);
+
+ if (group_event->attr.exclusive)
+ cpuctx->exclusive = 0;
+}
+
+/*
+ * Cross CPU call to remove a performance event
+ *
+ * We disable the event on the hardware level first. After that we
+ * remove it from the context list.
+ */
+static void __perf_event_remove_from_context(void *info)
+{
+ struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+ struct perf_event *event = info;
+ struct perf_event_context *ctx = event->ctx;
+
+ /*
+ * If this is a task context, we need to check whether it is
+ * the current task context of this cpu. If not it has been
+ * scheduled out before the smp call arrived.
+ */
+ if (ctx->task && cpuctx->task_ctx != ctx)
+ return;
+
+ spin_lock(&ctx->lock);
+ /*
+ * Protect the list operation against NMI by disabling the
+ * events on a global level.
+ */
+ perf_disable();
+
+ event_sched_out(event, cpuctx, ctx);
+
+ list_del_event(event, ctx);
+
+ if (!ctx->task) {
+ /*
+ * Allow more per task events with respect to the
+ * reservation:
+ */
+ cpuctx->max_pertask =
+ min(perf_max_events - ctx->nr_events,
+ perf_max_events - perf_reserved_percpu);
+ }
+
+ perf_enable();
+ spin_unlock(&ctx->lock);
+}
+
+
+/*
+ * Remove the event from a task's (or a CPU's) list of events.
+ *
+ * Must be called with ctx->mutex held.
+ *
+ * CPU events are removed with a smp call. For task events we only
+ * call when the task is on a CPU.
+ *
+ * If event->ctx is a cloned context, callers must make sure that
+ * every task struct that event->ctx->task could possibly point to
+ * remains valid. This is OK when called from perf_release since
+ * that only calls us on the top-level context, which can't be a clone.
+ * When called from perf_event_exit_task, it's OK because the
+ * context has been detached from its task.
+ */
+static void perf_event_remove_from_context(struct perf_event *event)
+{
+ struct perf_event_context *ctx = event->ctx;
+ struct task_struct *task = ctx->task;
+
+ if (!task) {
+ /*
+ * Per cpu events are removed via an smp call and
+ * the removal is always sucessful.
+ */
+ smp_call_function_single(event->cpu,
+ __perf_event_remove_from_context,
+ event, 1);
+ return;
+ }
+
+retry:
+ task_oncpu_function_call(task, __perf_event_remove_from_context,
+ event);
+
+ spin_lock_irq(&ctx->lock);
+ /*
+ * If the context is active we need to retry the smp call.
+ */
+ if (ctx->nr_active && !list_empty(&event->group_entry)) {
+ spin_unlock_irq(&ctx->lock);
+ goto retry;
+ }
+
+ /*
+ * The lock prevents that this context is scheduled in so we
+ * can remove the event safely, if the call above did not
+ * succeed.
+ */
+ if (!list_empty(&event->group_entry)) {
+ list_del_event(event, ctx);
+ }
+ spin_unlock_irq(&ctx->lock);
+}
+
+static inline u64 perf_clock(void)
+{
+ return cpu_clock(smp_processor_id());
+}
+
+/*
+ * Update the record of the current time in a context.
+ */
+static void update_context_time(struct perf_event_context *ctx)
+{
+ u64 now = perf_clock();
+
+ ctx->time += now - ctx->timestamp;
+ ctx->timestamp = now;
+}
+
+/*
+ * Update the total_time_enabled and total_time_running fields for a event.
+ */
+static void update_event_times(struct perf_event *event)
+{
+ struct perf_event_context *ctx = event->ctx;
+ u64 run_end;
+
+ if (event->state < PERF_EVENT_STATE_INACTIVE ||
+ event->group_leader->state < PERF_EVENT_STATE_INACTIVE)
+ return;
+
+ event->total_time_enabled = ctx->time - event->tstamp_enabled;
+
+ if (event->state == PERF_EVENT_STATE_INACTIVE)
+ run_end = event->tstamp_stopped;
+ else
+ run_end = ctx->time;
+
+ event->total_time_running = run_end - event->tstamp_running;
+}
+
+/*
+ * Update total_time_enabled and total_time_running for all events in a group.
+ */
+static void update_group_times(struct perf_event *leader)
+{
+ struct perf_event *event;
+
+ update_event_times(leader);
+ list_for_each_entry(event, &leader->sibling_list, group_entry)
+ update_event_times(event);
+}
+
+/*
+ * Cross CPU call to disable a performance event
+ */
+static void __perf_event_disable(void *info)
+{
+ struct perf_event *event = info;
+ struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+ struct perf_event_context *ctx = event->ctx;
+
+ /*
+ * If this is a per-task event, need to check whether this
+ * event's task is the current task on this cpu.
+ */
+ if (ctx->task && cpuctx->task_ctx != ctx)
+ return;
+
+ spin_lock(&ctx->lock);
+
+ /*
+ * If the event is on, turn it off.
+ * If it is in error state, leave it in error state.
+ */
+ if (event->state >= PERF_EVENT_STATE_INACTIVE) {
+ update_context_time(ctx);
+ update_group_times(event);
+ if (event == event->group_leader)
+ group_sched_out(event, cpuctx, ctx);
+ else
+ event_sched_out(event, cpuctx, ctx);
+ event->state = PERF_EVENT_STATE_OFF;
+ }
+
+ spin_unlock(&ctx->lock);
+}
+
+/*
+ * Disable a event.
+ *
+ * If event->ctx is a cloned context, callers must make sure that
+ * every task struct that event->ctx->task could possibly point to
+ * remains valid. This condition is satisifed when called through
+ * perf_event_for_each_child or perf_event_for_each because they
+ * hold the top-level event's child_mutex, so any descendant that
+ * goes to exit will block in sync_child_event.
+ * When called from perf_pending_event it's OK because event->ctx
+ * is the current context on this CPU and preemption is disabled,
+ * hence we can't get into perf_event_task_sched_out for this context.
+ */
+static void perf_event_disable(struct perf_event *event)
+{
+ struct perf_event_context *ctx = event->ctx;
+ struct task_struct *task = ctx->task;
+
+ if (!task) {
+ /*
+ * Disable the event on the cpu that it's on
+ */
+ smp_call_function_single(event->cpu, __perf_event_disable,
+ event, 1);
+ return;
+ }
+
+ retry:
+ task_oncpu_function_call(task, __perf_event_disable, event);
+
+ spin_lock_irq(&ctx->lock);
+ /*
+ * If the event is still active, we need to retry the cross-call.
+ */
+ if (event->state == PERF_EVENT_STATE_ACTIVE) {
+ spin_unlock_irq(&ctx->lock);
+ goto retry;
+ }
+
+ /*
+ * Since we have the lock this context can't be scheduled
+ * in, so we can change the state safely.
+ */
+ if (event->state == PERF_EVENT_STATE_INACTIVE) {
+ update_group_times(event);
+ event->state = PERF_EVENT_STATE_OFF;
+ }
+
+ spin_unlock_irq(&ctx->lock);
+}
+
+static int
+event_sched_in(struct perf_event *event,
+ struct perf_cpu_context *cpuctx,
+ struct perf_event_context *ctx,
+ int cpu)
+{
+ if (event->state <= PERF_EVENT_STATE_OFF)
+ return 0;
+
+ event->state = PERF_EVENT_STATE_ACTIVE;
+ event->oncpu = cpu; /* TODO: put 'cpu' into cpuctx->cpu */
+ /*
+ * The new state must be visible before we turn it on in the hardware:
+ */
+ smp_wmb();
+
+ if (event->pmu->enable(event)) {
+ event->state = PERF_EVENT_STATE_INACTIVE;
+ event->oncpu = -1;
+ return -EAGAIN;
+ }
+
+ event->tstamp_running += ctx->time - event->tstamp_stopped;
+
+ if (!is_software_event(event))
+ cpuctx->active_oncpu++;
+ ctx->nr_active++;
+
+ if (event->attr.exclusive)
+ cpuctx->exclusive = 1;
+
+ return 0;
+}
+
+static int
+group_sched_in(struct perf_event *group_event,
+ struct perf_cpu_context *cpuctx,
+ struct perf_event_context *ctx,
+ int cpu)
+{
+ struct perf_event *event, *partial_group;
+ int ret;
+
+ if (group_event->state == PERF_EVENT_STATE_OFF)
+ return 0;
+
+ ret = hw_perf_group_sched_in(group_event, cpuctx, ctx, cpu);
+ if (ret)
+ return ret < 0 ? ret : 0;
+
+ if (event_sched_in(group_event, cpuctx, ctx, cpu))
+ return -EAGAIN;
+
+ /*
+ * Schedule in siblings as one group (if any):
+ */
+ list_for_each_entry(event, &group_event->sibling_list, group_entry) {
+ if (event_sched_in(event, cpuctx, ctx, cpu)) {
+ partial_group = event;
+ goto group_error;
+ }
+ }
+
+ return 0;
+
+group_error:
+ /*
+ * Groups can be scheduled in as one unit only, so undo any
+ * partial group before returning:
+ */
+ list_for_each_entry(event, &group_event->sibling_list, group_entry) {
+ if (event == partial_group)
+ break;
+ event_sched_out(event, cpuctx, ctx);
+ }
+ event_sched_out(group_event, cpuctx, ctx);
+
+ return -EAGAIN;
+}
+
+/*
+ * Return 1 for a group consisting entirely of software events,
+ * 0 if the group contains any hardware events.
+ */
+static int is_software_only_group(struct perf_event *leader)
+{
+ struct perf_event *event;
+
+ if (!is_software_event(leader))
+ return 0;
+
+ list_for_each_entry(event, &leader->sibling_list, group_entry)
+ if (!is_software_event(event))
+ return 0;
+
+ return 1;
+}
+
+/*
+ * Work out whether we can put this event group on the CPU now.
+ */
+static int group_can_go_on(struct perf_event *event,
+ struct perf_cpu_context *cpuctx,
+ int can_add_hw)
+{
+ /*
+ * Groups consisting entirely of software events can always go on.
+ */
+ if (is_software_only_group(event))
+ return 1;
+ /*
+ * If an exclusive group is already on, no other hardware
+ * events can go on.
+ */
+ if (cpuctx->exclusive)
+ return 0;
+ /*
+ * If this group is exclusive and there are already
+ * events on the CPU, it can't go on.
+ */
+ if (event->attr.exclusive && cpuctx->active_oncpu)
+ return 0;
+ /*
+ * Otherwise, try to add it if all previous groups were able
+ * to go on.
+ */
+ return can_add_hw;
+}
+
+static void add_event_to_ctx(struct perf_event *event,
+ struct perf_event_context *ctx)
+{
+ list_add_event(event, ctx);
+ event->tstamp_enabled = ctx->time;
+ event->tstamp_running = ctx->time;
+ event->tstamp_stopped = ctx->time;
+}
+
+/*
+ * Cross CPU call to install and enable a performance event
+ *
+ * Must be called with ctx->mutex held
+ */
+static void __perf_install_in_context(void *info)
+{
+ struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+ struct perf_event *event = info;
+ struct perf_event_context *ctx = event->ctx;
+ struct perf_event *leader = event->group_leader;
+ int cpu = smp_processor_id();
+ int err;
+
+ /*
+ * If this is a task context, we need to check whether it is
+ * the current task context of this cpu. If not it has been
+ * scheduled out before the smp call arrived.
+ * Or possibly this is the right context but it isn't
+ * on this cpu because it had no events.
+ */
+ if (ctx->task && cpuctx->task_ctx != ctx) {
+ if (cpuctx->task_ctx || ctx->task != current)
+ return;
+ cpuctx->task_ctx = ctx;
+ }
+
+ spin_lock(&ctx->lock);
+ ctx->is_active = 1;
+ update_context_time(ctx);
+
+ /*
+ * Protect the list operation against NMI by disabling the
+ * events on a global level. NOP for non NMI based events.
+ */
+ perf_disable();
+
+ add_event_to_ctx(event, ctx);
+
+ /*
+ * Don't put the event on if it is disabled or if
+ * it is in a group and the group isn't on.
+ */
+ if (event->state != PERF_EVENT_STATE_INACTIVE ||
+ (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE))
+ goto unlock;
+
+ /*
+ * An exclusive event can't go on if there are already active
+ * hardware events, and no hardware event can go on if there
+ * is already an exclusive event on.
+ */
+ if (!group_can_go_on(event, cpuctx, 1))
+ err = -EEXIST;
+ else
+ err = event_sched_in(event, cpuctx, ctx, cpu);
+
+ if (err) {
+ /*
+ * This event couldn't go on. If it is in a group
+ * then we have to pull the whole group off.
+ * If the event group is pinned then put it in error state.
+ */
+ if (leader != event)
+ group_sched_out(leader, cpuctx, ctx);
+ if (leader->attr.pinned) {
+ update_group_times(leader);
+ leader->state = PERF_EVENT_STATE_ERROR;
+ }
+ }
+
+ if (!err && !ctx->task && cpuctx->max_pertask)
+ cpuctx->max_pertask--;
+
+ unlock:
+ perf_enable();
+
+ spin_unlock(&ctx->lock);
+}
+
+/*
+ * Attach a performance event to a context
+ *
+ * First we add the event to the list with the hardware enable bit
+ * in event->hw_config cleared.
+ *
+ * If the event is attached to a task which is on a CPU we use a smp
+ * call to enable it in the task context. The task might have been
+ * scheduled away, but we check this in the smp call again.
+ *
+ * Must be called with ctx->mutex held.
+ */
+static void
+perf_install_in_context(struct perf_event_context *ctx,
+ struct perf_event *event,
+ int cpu)
+{
+ struct task_struct *task = ctx->task;
+
+ if (!task) {
+ /*
+ * Per cpu events are installed via an smp call and
+ * the install is always sucessful.
+ */
+ smp_call_function_single(cpu, __perf_install_in_context,
+ event, 1);
+ return;
+ }
+
+retry:
+ task_oncpu_function_call(task, __perf_install_in_context,
+ event);
+
+ spin_lock_irq(&ctx->lock);
+ /*
+ * we need to retry the smp call.
+ */
+ if (ctx->is_active && list_empty(&event->group_entry)) {
+ spin_unlock_irq(&ctx->lock);
+ goto retry;
+ }
+
+ /*
+ * The lock prevents that this context is scheduled in so we
+ * can add the event safely, if it the call above did not
+ * succeed.
+ */
+ if (list_empty(&event->group_entry))
+ add_event_to_ctx(event, ctx);
+ spin_unlock_irq(&ctx->lock);
+}
+
+/*
+ * Put a event into inactive state and update time fields.
+ * Enabling the leader of a group effectively enables all
+ * the group members that aren't explicitly disabled, so we
+ * have to update their ->tstamp_enabled also.
+ * Note: this works for group members as well as group leaders
+ * since the non-leader members' sibling_lists will be empty.
+ */
+static void __perf_event_mark_enabled(struct perf_event *event,
+ struct perf_event_context *ctx)
+{
+ struct perf_event *sub;
+
+ event->state = PERF_EVENT_STATE_INACTIVE;
+ event->tstamp_enabled = ctx->time - event->total_time_enabled;
+ list_for_each_entry(sub, &event->sibling_list, group_entry)
+ if (sub->state >= PERF_EVENT_STATE_INACTIVE)
+ sub->tstamp_enabled =
+ ctx->time - sub->total_time_enabled;
+}
+
+/*
+ * Cross CPU call to enable a performance event
+ */
+static void __perf_event_enable(void *info)
+{
+ struct perf_event *event = info;
+ struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+ struct perf_event_context *ctx = event->ctx;
+ struct perf_event *leader = event->group_leader;
+ int err;
+
+ /*
+ * If this is a per-task event, need to check whether this
+ * event's task is the current task on this cpu.
+ */
+ if (ctx->task && cpuctx->task_ctx != ctx) {
+ if (cpuctx->task_ctx || ctx->task != current)
+ return;
+ cpuctx->task_ctx = ctx;
+ }
+
+ spin_lock(&ctx->lock);
+ ctx->is_active = 1;
+ update_context_time(ctx);
+
+ if (event->state >= PERF_EVENT_STATE_INACTIVE)
+ goto unlock;
+ __perf_event_mark_enabled(event, ctx);
+
+ /*
+ * If the event is in a group and isn't the group leader,
+ * then don't put it on unless the group is on.
+ */
+ if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE)
+ goto unlock;
+
+ if (!group_can_go_on(event, cpuctx, 1)) {
+ err = -EEXIST;
+ } else {
+ perf_disable();
+ if (event == leader)
+ err = group_sched_in(event, cpuctx, ctx,
+ smp_processor_id());
+ else
+ err = event_sched_in(event, cpuctx, ctx,
+ smp_processor_id());
+ perf_enable();
+ }
+
+ if (err) {
+ /*
+ * If this event can't go on and it's part of a
+ * group, then the whole group has to come off.
+ */
+ if (leader != event)
+ group_sched_out(leader, cpuctx, ctx);
+ if (leader->attr.pinned) {
+ update_group_times(leader);
+ leader->state = PERF_EVENT_STATE_ERROR;
+ }
+ }
+
+ unlock:
+ spin_unlock(&ctx->lock);
+}
+
+/*
+ * Enable a event.
+ *
+ * If event->ctx is a cloned context, callers must make sure that
+ * every task struct that event->ctx->task could possibly point to
+ * remains valid. This condition is satisfied when called through
+ * perf_event_for_each_child or perf_event_for_each as described
+ * for perf_event_disable.
+ */
+static void perf_event_enable(struct perf_event *event)
+{
+ struct perf_event_context *ctx = event->ctx;
+ struct task_struct *task = ctx->task;
+
+ if (!task) {
+ /*
+ * Enable the event on the cpu that it's on
+ */
+ smp_call_function_single(event->cpu, __perf_event_enable,
+ event, 1);
+ return;
+ }
+
+ spin_lock_irq(&ctx->lock);
+ if (event->state >= PERF_EVENT_STATE_INACTIVE)
+ goto out;
+
+ /*
+ * If the event is in error state, clear that first.
+ * That way, if we see the event in error state below, we
+ * know that it has gone back into error state, as distinct
+ * from the task having been scheduled away before the
+ * cross-call arrived.
+ */
+ if (event->state == PERF_EVENT_STATE_ERROR)
+ event->state = PERF_EVENT_STATE_OFF;
+
+ retry:
+ spin_unlock_irq(&ctx->lock);
+ task_oncpu_function_call(task, __perf_event_enable, event);
+
+ spin_lock_irq(&ctx->lock);
+
+ /*
+ * If the context is active and the event is still off,
+ * we need to retry the cross-call.
+ */
+ if (ctx->is_active && event->state == PERF_EVENT_STATE_OFF)
+ goto retry;
+
+ /*
+ * Since we have the lock this context can't be scheduled
+ * in, so we can change the state safely.
+ */
+ if (event->state == PERF_EVENT_STATE_OFF)
+ __perf_event_mark_enabled(event, ctx);
+
+ out:
+ spin_unlock_irq(&ctx->lock);
+}
+
+static int perf_event_refresh(struct perf_event *event, int refresh)
+{
+ /*
+ * not supported on inherited events
+ */
+ if (event->attr.inherit)
+ return -EINVAL;
+
+ atomic_add(refresh, &event->event_limit);
+ perf_event_enable(event);
+
+ return 0;
+}
+
+void __perf_event_sched_out(struct perf_event_context *ctx,
+ struct perf_cpu_context *cpuctx)
+{
+ struct perf_event *event;
+
+ spin_lock(&ctx->lock);
+ ctx->is_active = 0;
+ if (likely(!ctx->nr_events))
+ goto out;
+ update_context_time(ctx);
+
+ perf_disable();
+ if (ctx->nr_active) {
+ list_for_each_entry(event, &ctx->group_list, group_entry) {
+ if (event != event->group_leader)
+ event_sched_out(event, cpuctx, ctx);
+ else
+ group_sched_out(event, cpuctx, ctx);
+ }
+ }
+ perf_enable();
+ out:
+ spin_unlock(&ctx->lock);
+}
+
+/*
+ * Test whether two contexts are equivalent, i.e. whether they
+ * have both been cloned from the same version of the same context
+ * and they both have the same number of enabled events.
+ * If the number of enabled events is the same, then the set
+ * of enabled events should be the same, because these are both
+ * inherited contexts, therefore we can't access individual events
+ * in them directly with an fd; we can only enable/disable all
+ * events via prctl, or enable/disable all events in a family
+ * via ioctl, which will have the same effect on both contexts.
+ */
+static int context_equiv(struct perf_event_context *ctx1,
+ struct perf_event_context *ctx2)
+{
+ return ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx
+ && ctx1->parent_gen == ctx2->parent_gen
+ && !ctx1->pin_count && !ctx2->pin_count;
+}
+
+static void __perf_event_read(void *event);
+
+static void __perf_event_sync_stat(struct perf_event *event,
+ struct perf_event *next_event)
+{
+ u64 value;
+
+ if (!event->attr.inherit_stat)
+ return;
+
+ /*
+ * Update the event value, we cannot use perf_event_read()
+ * because we're in the middle of a context switch and have IRQs
+ * disabled, which upsets smp_call_function_single(), however
+ * we know the event must be on the current CPU, therefore we
+ * don't need to use it.
+ */
+ switch (event->state) {
+ case PERF_EVENT_STATE_ACTIVE:
+ __perf_event_read(event);
+ break;
+
+ case PERF_EVENT_STATE_INACTIVE:
+ update_event_times(event);
+ break;
+
+ default:
+ break;
+ }
+
+ /*
+ * In order to keep per-task stats reliable we need to flip the event
+ * values when we flip the contexts.
+ */
+ value = atomic64_read(&next_event->count);
+ value = atomic64_xchg(&event->count, value);
+ atomic64_set(&next_event->count, value);
+
+ swap(event->total_time_enabled, next_event->total_time_enabled);
+ swap(event->total_time_running, next_event->total_time_running);
+
+ /*
+ * Since we swizzled the values, update the user visible data too.
+ */
+ perf_event_update_userpage(event);
+ perf_event_update_userpage(next_event);
+}
+
+#define list_next_entry(pos, member) \
+ list_entry(pos->member.next, typeof(*pos), member)
+
+static void perf_event_sync_stat(struct perf_event_context *ctx,
+ struct perf_event_context *next_ctx)
+{
+ struct perf_event *event, *next_event;
+
+ if (!ctx->nr_stat)
+ return;
+
+ event = list_first_entry(&ctx->event_list,
+ struct perf_event, event_entry);
+
+ next_event = list_first_entry(&next_ctx->event_list,
+ struct perf_event, event_entry);
+
+ while (&event->event_entry != &ctx->event_list &&
+ &next_event->event_entry != &next_ctx->event_list) {
+
+ __perf_event_sync_stat(event, next_event);
+
+ event = list_next_entry(event, event_entry);
+ next_event = list_next_entry(next_event, event_entry);
+ }
+}
+
+/*
+ * Called from scheduler to remove the events of the current task,
+ * with interrupts disabled.
+ *
+ * We stop each event and update the event value in event->count.
+ *
+ * This does not protect us against NMI, but disable()
+ * sets the disabled bit in the control field of event _before_
+ * accessing the event control register. If a NMI hits, then it will
+ * not restart the event.
+ */
+void perf_event_task_sched_out(struct task_struct *task,
+ struct task_struct *next, int cpu)
+{
+ struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
+ struct perf_event_context *ctx = task->perf_event_ctxp;
+ struct perf_event_context *next_ctx;
+ struct perf_event_context *parent;
+ struct pt_regs *regs;
+ int do_switch = 1;
+
+ regs = task_pt_regs(task);
+ perf_sw_event(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 1, regs, 0);
+
+ if (likely(!ctx || !cpuctx->task_ctx))
+ return;
+
+ update_context_time(ctx);
+
+ rcu_read_lock();
+ parent = rcu_dereference(ctx->parent_ctx);
+ next_ctx = next->perf_event_ctxp;
+ if (parent && next_ctx &&
+ rcu_dereference(next_ctx->parent_ctx) == parent) {
+ /*
+ * Looks like the two contexts are clones, so we might be
+ * able to optimize the context switch. We lock both
+ * contexts and check that they are clones under the
+ * lock (including re-checking that neither has been
+ * uncloned in the meantime). It doesn't matter which
+ * order we take the locks because no other cpu could
+ * be trying to lock both of these tasks.
+ */
+ spin_lock(&ctx->lock);
+ spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING);
+ if (context_equiv(ctx, next_ctx)) {
+ /*
+ * XXX do we need a memory barrier of sorts
+ * wrt to rcu_dereference() of perf_event_ctxp
+ */
+ task->perf_event_ctxp = next_ctx;
+ next->perf_event_ctxp = ctx;
+ ctx->task = next;
+ next_ctx->task = task;
+ do_switch = 0;
+
+ perf_event_sync_stat(ctx, next_ctx);
+ }
+ spin_unlock(&next_ctx->lock);
+ spin_unlock(&ctx->lock);
+ }
+ rcu_read_unlock();
+
+ if (do_switch) {
+ __perf_event_sched_out(ctx, cpuctx);
+ cpuctx->task_ctx = NULL;
+ }
+}
+
+/*
+ * Called with IRQs disabled
+ */
+static void __perf_event_task_sched_out(struct perf_event_context *ctx)
+{
+ struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+
+ if (!cpuctx->task_ctx)
+ return;
+
+ if (WARN_ON_ONCE(ctx != cpuctx->task_ctx))
+ return;
+
+ __perf_event_sched_out(ctx, cpuctx);
+ cpuctx->task_ctx = NULL;
+}
+
+/*
+ * Called with IRQs disabled
+ */
+static void perf_event_cpu_sched_out(struct perf_cpu_context *cpuctx)
+{
+ __perf_event_sched_out(&cpuctx->ctx, cpuctx);
+}
+
+static void
+__perf_event_sched_in(struct perf_event_context *ctx,
+ struct perf_cpu_context *cpuctx, int cpu)
+{
+ struct perf_event *event;
+ int can_add_hw = 1;
+
+ spin_lock(&ctx->lock);
+ ctx->is_active = 1;
+ if (likely(!ctx->nr_events))
+ goto out;
+
+ ctx->timestamp = perf_clock();
+
+ perf_disable();
+
+ /*
+ * First go through the list and put on any pinned groups
+ * in order to give them the best chance of going on.
+ */
+ list_for_each_entry(event, &ctx->group_list, group_entry) {
+ if (event->state <= PERF_EVENT_STATE_OFF ||
+ !event->attr.pinned)
+ continue;
+ if (event->cpu != -1 && event->cpu != cpu)
+ continue;
+
+ if (event != event->group_leader)
+ event_sched_in(event, cpuctx, ctx, cpu);
+ else {
+ if (group_can_go_on(event, cpuctx, 1))
+ group_sched_in(event, cpuctx, ctx, cpu);
+ }
+
+ /*
+ * If this pinned group hasn't been scheduled,
+ * put it in error state.
+ */
+ if (event->state == PERF_EVENT_STATE_INACTIVE) {
+ update_group_times(event);
+ event->state = PERF_EVENT_STATE_ERROR;
+ }
+ }
+
+ list_for_each_entry(event, &ctx->group_list, group_entry) {
+ /*
+ * Ignore events in OFF or ERROR state, and
+ * ignore pinned events since we did them already.
+ */
+ if (event->state <= PERF_EVENT_STATE_OFF ||
+ event->attr.pinned)
+ continue;
+
+ /*
+ * Listen to the 'cpu' scheduling filter constraint
+ * of events:
+ */
+ if (event->cpu != -1 && event->cpu != cpu)
+ continue;
+
+ if (event != event->group_leader) {
+ if (event_sched_in(event, cpuctx, ctx, cpu))
+ can_add_hw = 0;
+ } else {
+ if (group_can_go_on(event, cpuctx, can_add_hw)) {
+ if (group_sched_in(event, cpuctx, ctx, cpu))
+ can_add_hw = 0;
+ }
+ }
+ }
+ perf_enable();
+ out:
+ spin_unlock(&ctx->lock);
+}
+
+/*
+ * Called from scheduler to add the events of the current task
+ * with interrupts disabled.
+ *
+ * We restore the event value and then enable it.
+ *
+ * This does not protect us against NMI, but enable()
+ * sets the enabled bit in the control field of event _before_
+ * accessing the event control register. If a NMI hits, then it will
+ * keep the event running.
+ */
+void perf_event_task_sched_in(struct task_struct *task, int cpu)
+{
+ struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
+ struct perf_event_context *ctx = task->perf_event_ctxp;
+
+ if (likely(!ctx))
+ return;
+ if (cpuctx->task_ctx == ctx)
+ return;
+ __perf_event_sched_in(ctx, cpuctx, cpu);
+ cpuctx->task_ctx = ctx;
+}
+
+static void perf_event_cpu_sched_in(struct perf_cpu_context *cpuctx, int cpu)
+{
+ struct perf_event_context *ctx = &cpuctx->ctx;
+
+ __perf_event_sched_in(ctx, cpuctx, cpu);
+}
+
+#define MAX_INTERRUPTS (~0ULL)
+
+static void perf_log_throttle(struct perf_event *event, int enable);
+
+static void perf_adjust_period(struct perf_event *event, u64 events)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ u64 period, sample_period;
+ s64 delta;
+
+ events *= hwc->sample_period;
+ period = div64_u64(events, event->attr.sample_freq);
+
+ delta = (s64)(period - hwc->sample_period);
+ delta = (delta + 7) / 8; /* low pass filter */
+
+ sample_period = hwc->sample_period + delta;
+
+ if (!sample_period)
+ sample_period = 1;
+
+ hwc->sample_period = sample_period;
+}
+
+static void perf_ctx_adjust_freq(struct perf_event_context *ctx)
+{
+ struct perf_event *event;
+ struct hw_perf_event *hwc;
+ u64 interrupts, freq;
+
+ spin_lock(&ctx->lock);
+ list_for_each_entry(event, &ctx->group_list, group_entry) {
+ if (event->state != PERF_EVENT_STATE_ACTIVE)
+ continue;
+
+ hwc = &event->hw;
+
+ interrupts = hwc->interrupts;
+ hwc->interrupts = 0;
+
+ /*
+ * unthrottle events on the tick
+ */
+ if (interrupts == MAX_INTERRUPTS) {
+ perf_log_throttle(event, 1);
+ event->pmu->unthrottle(event);
+ interrupts = 2*sysctl_perf_event_sample_rate/HZ;
+ }
+
+ if (!event->attr.freq || !event->attr.sample_freq)
+ continue;
+
+ /*
+ * if the specified freq < HZ then we need to skip ticks
+ */
+ if (event->attr.sample_freq < HZ) {
+ freq = event->attr.sample_freq;
+
+ hwc->freq_count += freq;
+ hwc->freq_interrupts += interrupts;
+
+ if (hwc->freq_count < HZ)
+ continue;
+
+ interrupts = hwc->freq_interrupts;
+ hwc->freq_interrupts = 0;
+ hwc->freq_count -= HZ;
+ } else
+ freq = HZ;
+
+ perf_adjust_period(event, freq * interrupts);
+
+ /*
+ * In order to avoid being stalled by an (accidental) huge
+ * sample period, force reset the sample period if we didn't
+ * get any events in this freq period.
+ */
+ if (!interrupts) {
+ perf_disable();
+ event->pmu->disable(event);
+ atomic64_set(&hwc->period_left, 0);
+ event->pmu->enable(event);
+ perf_enable();
+ }
+ }
+ spin_unlock(&ctx->lock);
+}
+
+/*
+ * Round-robin a context's events:
+ */
+static void rotate_ctx(struct perf_event_context *ctx)
+{
+ struct perf_event *event;
+
+ if (!ctx->nr_events)
+ return;
+
+ spin_lock(&ctx->lock);
+ /*
+ * Rotate the first entry last (works just fine for group events too):
+ */
+ perf_disable();
+ list_for_each_entry(event, &ctx->group_list, group_entry) {
+ list_move_tail(&event->group_entry, &ctx->group_list);
+ break;
+ }
+ perf_enable();
+
+ spin_unlock(&ctx->lock);
+}
+
+void perf_event_task_tick(struct task_struct *curr, int cpu)
+{
+ struct perf_cpu_context *cpuctx;
+ struct perf_event_context *ctx;
+
+ if (!atomic_read(&nr_events))
+ return;
+
+ cpuctx = &per_cpu(perf_cpu_context, cpu);
+ ctx = curr->perf_event_ctxp;
+
+ perf_ctx_adjust_freq(&cpuctx->ctx);
+ if (ctx)
+ perf_ctx_adjust_freq(ctx);
+
+ perf_event_cpu_sched_out(cpuctx);
+ if (ctx)
+ __perf_event_task_sched_out(ctx);
+
+ rotate_ctx(&cpuctx->ctx);
+ if (ctx)
+ rotate_ctx(ctx);
+
+ perf_event_cpu_sched_in(cpuctx, cpu);
+ if (ctx)
+ perf_event_task_sched_in(curr, cpu);
+}
+
+/*
+ * Enable all of a task's events that have been marked enable-on-exec.
+ * This expects task == current.
+ */
+static void perf_event_enable_on_exec(struct task_struct *task)
+{
+ struct perf_event_context *ctx;
+ struct perf_event *event;
+ unsigned long flags;
+ int enabled = 0;
+
+ local_irq_save(flags);
+ ctx = task->perf_event_ctxp;
+ if (!ctx || !ctx->nr_events)
+ goto out;
+
+ __perf_event_task_sched_out(ctx);
+
+ spin_lock(&ctx->lock);
+
+ list_for_each_entry(event, &ctx->group_list, group_entry) {
+ if (!event->attr.enable_on_exec)
+ continue;
+ event->attr.enable_on_exec = 0;
+ if (event->state >= PERF_EVENT_STATE_INACTIVE)
+ continue;
+ __perf_event_mark_enabled(event, ctx);
+ enabled = 1;
+ }
+
+ /*
+ * Unclone this context if we enabled any event.
+ */
+ if (enabled)
+ unclone_ctx(ctx);
+
+ spin_unlock(&ctx->lock);
+
+ perf_event_task_sched_in(task, smp_processor_id());
+ out:
+ local_irq_restore(flags);
+}
+
+/*
+ * Cross CPU call to read the hardware event
+ */
+static void __perf_event_read(void *info)
+{
+ struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+ struct perf_event *event = info;
+ struct perf_event_context *ctx = event->ctx;
+ unsigned long flags;
+
+ /*
+ * If this is a task context, we need to check whether it is
+ * the current task context of this cpu. If not it has been
+ * scheduled out before the smp call arrived. In that case
+ * event->count would have been updated to a recent sample
+ * when the event was scheduled out.
+ */
+ if (ctx->task && cpuctx->task_ctx != ctx)
+ return;
+
+ local_irq_save(flags);
+ if (ctx->is_active)
+ update_context_time(ctx);
+ event->pmu->read(event);
+ update_event_times(event);
+ local_irq_restore(flags);
+}
+
+static u64 perf_event_read(struct perf_event *event)
+{
+ /*
+ * If event is enabled and currently active on a CPU, update the
+ * value in the event structure:
+ */
+ if (event->state == PERF_EVENT_STATE_ACTIVE) {
+ smp_call_function_single(event->oncpu,
+ __perf_event_read, event, 1);
+ } else if (event->state == PERF_EVENT_STATE_INACTIVE) {
+ update_event_times(event);
+ }
+
+ return atomic64_read(&event->count);
+}
+
+/*
+ * Initialize the perf_event context in a task_struct:
+ */
+static void
+__perf_event_init_context(struct perf_event_context *ctx,
+ struct task_struct *task)
+{
+ memset(ctx, 0, sizeof(*ctx));
+ spin_lock_init(&ctx->lock);
+ mutex_init(&ctx->mutex);
+ INIT_LIST_HEAD(&ctx->group_list);
+ INIT_LIST_HEAD(&ctx->event_list);
+ atomic_set(&ctx->refcount, 1);
+ ctx->task = task;
+}
+
+static struct perf_event_context *find_get_context(pid_t pid, int cpu)
+{
+ struct perf_event_context *ctx;
+ struct perf_cpu_context *cpuctx;
+ struct task_struct *task;
+ unsigned long flags;
+ int err;
+
+ /*
+ * If cpu is not a wildcard then this is a percpu event:
+ */
+ if (cpu != -1) {
+ /* Must be root to operate on a CPU event: */
+ if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN))
+ return ERR_PTR(-EACCES);
+
+ if (cpu < 0 || cpu > num_possible_cpus())
+ return ERR_PTR(-EINVAL);
+
+ /*
+ * We could be clever and allow to attach a event to an
+ * offline CPU and activate it when the CPU comes up, but
+ * that's for later.
+ */
+ if (!cpu_isset(cpu, cpu_online_map))
+ return ERR_PTR(-ENODEV);
+
+ cpuctx = &per_cpu(perf_cpu_context, cpu);
+ ctx = &cpuctx->ctx;
+ get_ctx(ctx);
+
+ return ctx;
+ }
+
+ rcu_read_lock();
+ if (!pid)
+ task = current;
+ else
+ task = find_task_by_vpid(pid);
+ if (task)
+ get_task_struct(task);
+ rcu_read_unlock();
+
+ if (!task)
+ return ERR_PTR(-ESRCH);
+
+ /*
+ * Can't attach events to a dying task.
+ */
+ err = -ESRCH;
+ if (task->flags & PF_EXITING)
+ goto errout;
+
+ /* Reuse ptrace permission checks for now. */
+ err = -EACCES;
+ if (!ptrace_may_access(task, PTRACE_MODE_READ))
+ goto errout;
+
+ retry:
+ ctx = perf_lock_task_context(task, &flags);
+ if (ctx) {
+ unclone_ctx(ctx);
+ spin_unlock_irqrestore(&ctx->lock, flags);
+ }
+
+ if (!ctx) {
+ ctx = kmalloc(sizeof(struct perf_event_context), GFP_KERNEL);
+ err = -ENOMEM;
+ if (!ctx)
+ goto errout;
+ __perf_event_init_context(ctx, task);
+ get_ctx(ctx);
+ if (cmpxchg(&task->perf_event_ctxp, NULL, ctx)) {
+ /*
+ * We raced with some other task; use
+ * the context they set.
+ */
+ kfree(ctx);
+ goto retry;
+ }
+ get_task_struct(task);
+ }
+
+ put_task_struct(task);
+ return ctx;
+
+ errout:
+ put_task_struct(task);
+ return ERR_PTR(err);
+}
+
+static void free_event_rcu(struct rcu_head *head)
+{
+ struct perf_event *event;
+
+ event = container_of(head, struct perf_event, rcu_head);
+ if (event->ns)
+ put_pid_ns(event->ns);
+ kfree(event);
+}
+
+static void perf_pending_sync(struct perf_event *event);
+
+static void free_event(struct perf_event *event)
+{
+ perf_pending_sync(event);
+
+ if (!event->parent) {
+ atomic_dec(&nr_events);
+ if (event->attr.mmap)
+ atomic_dec(&nr_mmap_events);
+ if (event->attr.comm)
+ atomic_dec(&nr_comm_events);
+ if (event->attr.task)
+ atomic_dec(&nr_task_events);
+ }
+
+ if (event->output) {
+ fput(event->output->filp);
+ event->output = NULL;
+ }
+
+ if (event->destroy)
+ event->destroy(event);
+
+ put_ctx(event->ctx);
+ call_rcu(&event->rcu_head, free_event_rcu);
+}
+
+/*
+ * Called when the last reference to the file is gone.
+ */
+static int perf_release(struct inode *inode, struct file *file)
+{
+ struct perf_event *event = file->private_data;
+ struct perf_event_context *ctx = event->ctx;
+
+ file->private_data = NULL;
+
+ WARN_ON_ONCE(ctx->parent_ctx);
+ mutex_lock(&ctx->mutex);
+ perf_event_remove_from_context(event);
+ mutex_unlock(&ctx->mutex);
+
+ mutex_lock(&event->owner->perf_event_mutex);
+ list_del_init(&event->owner_entry);
+ mutex_unlock(&event->owner->perf_event_mutex);
+ put_task_struct(event->owner);
+
+ free_event(event);
+
+ return 0;
+}
+
+static int perf_event_read_size(struct perf_event *event)
+{
+ int entry = sizeof(u64); /* value */
+ int size = 0;
+ int nr = 1;
+
+ if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+ size += sizeof(u64);
+
+ if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+ size += sizeof(u64);
+
+ if (event->attr.read_format & PERF_FORMAT_ID)
+ entry += sizeof(u64);
+
+ if (event->attr.read_format & PERF_FORMAT_GROUP) {
+ nr += event->group_leader->nr_siblings;
+ size += sizeof(u64);
+ }
+
+ size += entry * nr;
+
+ return size;
+}
+
+static u64 perf_event_read_value(struct perf_event *event)
+{
+ struct perf_event *child;
+ u64 total = 0;
+
+ total += perf_event_read(event);
+ list_for_each_entry(child, &event->child_list, child_list)
+ total += perf_event_read(child);
+
+ return total;
+}
+
+static int perf_event_read_entry(struct perf_event *event,
+ u64 read_format, char __user *buf)
+{
+ int n = 0, count = 0;
+ u64 values[2];
+
+ values[n++] = perf_event_read_value(event);
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_event_id(event);
+
+ count = n * sizeof(u64);
+
+ if (copy_to_user(buf, values, count))
+ return -EFAULT;
+
+ return count;
+}
+
+static int perf_event_read_group(struct perf_event *event,
+ u64 read_format, char __user *buf)
+{
+ struct perf_event *leader = event->group_leader, *sub;
+ int n = 0, size = 0, err = -EFAULT;
+ u64 values[3];
+
+ values[n++] = 1 + leader->nr_siblings;
+ if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
+ values[n++] = leader->total_time_enabled +
+ atomic64_read(&leader->child_total_time_enabled);
+ }
+ if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
+ values[n++] = leader->total_time_running +
+ atomic64_read(&leader->child_total_time_running);
+ }
+
+ size = n * sizeof(u64);
+
+ if (copy_to_user(buf, values, size))
+ return -EFAULT;
+
+ err = perf_event_read_entry(leader, read_format, buf + size);
+ if (err < 0)
+ return err;
+
+ size += err;
+
+ list_for_each_entry(sub, &leader->sibling_list, group_entry) {
+ err = perf_event_read_entry(sub, read_format,
+ buf + size);
+ if (err < 0)
+ return err;
+
+ size += err;
+ }
+
+ return size;
+}
+
+static int perf_event_read_one(struct perf_event *event,
+ u64 read_format, char __user *buf)
+{
+ u64 values[4];
+ int n = 0;
+
+ values[n++] = perf_event_read_value(event);
+ if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
+ values[n++] = event->total_time_enabled +
+ atomic64_read(&event->child_total_time_enabled);
+ }
+ if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
+ values[n++] = event->total_time_running +
+ atomic64_read(&event->child_total_time_running);
+ }
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_event_id(event);
+
+ if (copy_to_user(buf, values, n * sizeof(u64)))
+ return -EFAULT;
+
+ return n * sizeof(u64);
+}
+
+/*
+ * Read the performance event - simple non blocking version for now
+ */
+static ssize_t
+perf_read_hw(struct perf_event *event, char __user *buf, size_t count)
+{
+ u64 read_format = event->attr.read_format;
+ int ret;
+
+ /*
+ * Return end-of-file for a read on a event that is in
+ * error state (i.e. because it was pinned but it couldn't be
+ * scheduled on to the CPU at some point).
+ */
+ if (event->state == PERF_EVENT_STATE_ERROR)
+ return 0;
+
+ if (count < perf_event_read_size(event))
+ return -ENOSPC;
+
+ WARN_ON_ONCE(event->ctx->parent_ctx);
+ mutex_lock(&event->child_mutex);
+ if (read_format & PERF_FORMAT_GROUP)
+ ret = perf_event_read_group(event, read_format, buf);
+ else
+ ret = perf_event_read_one(event, read_format, buf);
+ mutex_unlock(&event->child_mutex);
+
+ return ret;
+}
+
+static ssize_t
+perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
+{
+ struct perf_event *event = file->private_data;
+
+ return perf_read_hw(event, buf, count);
+}
+
+static unsigned int perf_poll(struct file *file, poll_table *wait)
+{
+ struct perf_event *event = file->private_data;
+ struct perf_mmap_data *data;
+ unsigned int events = POLL_HUP;
+
+ rcu_read_lock();
+ data = rcu_dereference(event->data);
+ if (data)
+ events = atomic_xchg(&data->poll, 0);
+ rcu_read_unlock();
+
+ poll_wait(file, &event->waitq, wait);
+
+ return events;
+}
+
+static void perf_event_reset(struct perf_event *event)
+{
+ (void)perf_event_read(event);
+ atomic64_set(&event->count, 0);
+ perf_event_update_userpage(event);
+}
+
+/*
+ * Holding the top-level event's child_mutex means that any
+ * descendant process that has inherited this event will block
+ * in sync_child_event if it goes to exit, thus satisfying the
+ * task existence requirements of perf_event_enable/disable.
+ */
+static void perf_event_for_each_child(struct perf_event *event,
+ void (*func)(struct perf_event *))
+{
+ struct perf_event *child;
+
+ WARN_ON_ONCE(event->ctx->parent_ctx);
+ mutex_lock(&event->child_mutex);
+ func(event);
+ list_for_each_entry(child, &event->child_list, child_list)
+ func(child);
+ mutex_unlock(&event->child_mutex);
+}
+
+static void perf_event_for_each(struct perf_event *event,
+ void (*func)(struct perf_event *))
+{
+ struct perf_event_context *ctx = event->ctx;
+ struct perf_event *sibling;
+
+ WARN_ON_ONCE(ctx->parent_ctx);
+ mutex_lock(&ctx->mutex);
+ event = event->group_leader;
+
+ perf_event_for_each_child(event, func);
+ func(event);
+ list_for_each_entry(sibling, &event->sibling_list, group_entry)
+ perf_event_for_each_child(event, func);
+ mutex_unlock(&ctx->mutex);
+}
+
+static int perf_event_period(struct perf_event *event, u64 __user *arg)
+{
+ struct perf_event_context *ctx = event->ctx;
+ unsigned long size;
+ int ret = 0;
+ u64 value;
+
+ if (!event->attr.sample_period)
+ return -EINVAL;
+
+ size = copy_from_user(&value, arg, sizeof(value));
+ if (size != sizeof(value))
+ return -EFAULT;
+
+ if (!value)
+ return -EINVAL;
+
+ spin_lock_irq(&ctx->lock);
+ if (event->attr.freq) {
+ if (value > sysctl_perf_event_sample_rate) {
+ ret = -EINVAL;
+ goto unlock;
+ }
+
+ event->attr.sample_freq = value;
+ } else {
+ event->attr.sample_period = value;
+ event->hw.sample_period = value;
+ }
+unlock:
+ spin_unlock_irq(&ctx->lock);
+
+ return ret;
+}
+
+int perf_event_set_output(struct perf_event *event, int output_fd);
+
+static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct perf_event *event = file->private_data;
+ void (*func)(struct perf_event *);
+ u32 flags = arg;
+
+ switch (cmd) {
+ case PERF_EVENT_IOC_ENABLE:
+ func = perf_event_enable;
+ break;
+ case PERF_EVENT_IOC_DISABLE:
+ func = perf_event_disable;
+ break;
+ case PERF_EVENT_IOC_RESET:
+ func = perf_event_reset;
+ break;
+
+ case PERF_EVENT_IOC_REFRESH:
+ return perf_event_refresh(event, arg);
+
+ case PERF_EVENT_IOC_PERIOD:
+ return perf_event_period(event, (u64 __user *)arg);
+
+ case PERF_EVENT_IOC_SET_OUTPUT:
+ return perf_event_set_output(event, arg);
+
+ default:
+ return -ENOTTY;
+ }
+
+ if (flags & PERF_IOC_FLAG_GROUP)
+ perf_event_for_each(event, func);
+ else
+ perf_event_for_each_child(event, func);
+
+ return 0;
+}
+
+int perf_event_task_enable(void)
+{
+ struct perf_event *event;
+
+ mutex_lock(&current->perf_event_mutex);
+ list_for_each_entry(event, &current->perf_event_list, owner_entry)
+ perf_event_for_each_child(event, perf_event_enable);
+ mutex_unlock(&current->perf_event_mutex);
+
+ return 0;
+}
+
+int perf_event_task_disable(void)
+{
+ struct perf_event *event;
+
+ mutex_lock(&current->perf_event_mutex);
+ list_for_each_entry(event, &current->perf_event_list, owner_entry)
+ perf_event_for_each_child(event, perf_event_disable);
+ mutex_unlock(&current->perf_event_mutex);
+
+ return 0;
+}
+
+#ifndef PERF_EVENT_INDEX_OFFSET
+# define PERF_EVENT_INDEX_OFFSET 0
+#endif
+
+static int perf_event_index(struct perf_event *event)
+{
+ if (event->state != PERF_EVENT_STATE_ACTIVE)
+ return 0;
+
+ return event->hw.idx + 1 - PERF_EVENT_INDEX_OFFSET;
+}
+
+/*
+ * Callers need to ensure there can be no nesting of this function, otherwise
+ * the seqlock logic goes bad. We can not serialize this because the arch
+ * code calls this from NMI context.
+ */
+void perf_event_update_userpage(struct perf_event *event)
+{
+ struct perf_event_mmap_page *userpg;
+ struct perf_mmap_data *data;
+
+ rcu_read_lock();
+ data = rcu_dereference(event->data);
+ if (!data)
+ goto unlock;
+
+ userpg = data->user_page;
+
+ /*
+ * Disable preemption so as to not let the corresponding user-space
+ * spin too long if we get preempted.
+ */
+ preempt_disable();
+ ++userpg->lock;
+ barrier();
+ userpg->index = perf_event_index(event);
+ userpg->offset = atomic64_read(&event->count);
+ if (event->state == PERF_EVENT_STATE_ACTIVE)
+ userpg->offset -= atomic64_read(&event->hw.prev_count);
+
+ userpg->time_enabled = event->total_time_enabled +
+ atomic64_read(&event->child_total_time_enabled);
+
+ userpg->time_running = event->total_time_running +
+ atomic64_read(&event->child_total_time_running);
+
+ barrier();
+ ++userpg->lock;
+ preempt_enable();
+unlock:
+ rcu_read_unlock();
+}
+
+static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct perf_event *event = vma->vm_file->private_data;
+ struct perf_mmap_data *data;
+ int ret = VM_FAULT_SIGBUS;
+
+ if (vmf->flags & FAULT_FLAG_MKWRITE) {
+ if (vmf->pgoff == 0)
+ ret = 0;
+ return ret;
+ }
+
+ rcu_read_lock();
+ data = rcu_dereference(event->data);
+ if (!data)
+ goto unlock;
+
+ if (vmf->pgoff == 0) {
+ vmf->page = virt_to_page(data->user_page);
+ } else {
+ int nr = vmf->pgoff - 1;
+
+ if ((unsigned)nr > data->nr_pages)
+ goto unlock;
+
+ if (vmf->flags & FAULT_FLAG_WRITE)
+ goto unlock;
+
+ vmf->page = virt_to_page(data->data_pages[nr]);
+ }
+
+ get_page(vmf->page);
+ vmf->page->mapping = vma->vm_file->f_mapping;
+ vmf->page->index = vmf->pgoff;
+
+ ret = 0;
+unlock:
+ rcu_read_unlock();
+
+ return ret;
+}
+
+static int perf_mmap_data_alloc(struct perf_event *event, int nr_pages)
+{
+ struct perf_mmap_data *data;
+ unsigned long size;
+ int i;
+
+ WARN_ON(atomic_read(&event->mmap_count));
+
+ size = sizeof(struct perf_mmap_data);
+ size += nr_pages * sizeof(void *);
+
+ data = kzalloc(size, GFP_KERNEL);
+ if (!data)
+ goto fail;
+
+ data->user_page = (void *)get_zeroed_page(GFP_KERNEL);
+ if (!data->user_page)
+ goto fail_user_page;
+
+ for (i = 0; i < nr_pages; i++) {
+ data->data_pages[i] = (void *)get_zeroed_page(GFP_KERNEL);
+ if (!data->data_pages[i])
+ goto fail_data_pages;
+ }
+
+ data->nr_pages = nr_pages;
+ atomic_set(&data->lock, -1);
+
+ if (event->attr.watermark) {
+ data->watermark = min_t(long, PAGE_SIZE * nr_pages,
+ event->attr.wakeup_watermark);
+ }
+ if (!data->watermark)
+ data->watermark = max(PAGE_SIZE, PAGE_SIZE * nr_pages / 4);
+
+ rcu_assign_pointer(event->data, data);
+
+ return 0;
+
+fail_data_pages:
+ for (i--; i >= 0; i--)
+ free_page((unsigned long)data->data_pages[i]);
+
+ free_page((unsigned long)data->user_page);
+
+fail_user_page:
+ kfree(data);
+
+fail:
+ return -ENOMEM;
+}
+
+static void perf_mmap_free_page(unsigned long addr)
+{
+ struct page *page = virt_to_page((void *)addr);
+
+ page->mapping = NULL;
+ __free_page(page);
+}
+
+static void __perf_mmap_data_free(struct rcu_head *rcu_head)
+{
+ struct perf_mmap_data *data;
+ int i;
+
+ data = container_of(rcu_head, struct perf_mmap_data, rcu_head);
+
+ perf_mmap_free_page((unsigned long)data->user_page);
+ for (i = 0; i < data->nr_pages; i++)
+ perf_mmap_free_page((unsigned long)data->data_pages[i]);
+
+ kfree(data);
+}
+
+static void perf_mmap_data_free(struct perf_event *event)
+{
+ struct perf_mmap_data *data = event->data;
+
+ WARN_ON(atomic_read(&event->mmap_count));
+
+ rcu_assign_pointer(event->data, NULL);
+ call_rcu(&data->rcu_head, __perf_mmap_data_free);
+}
+
+static void perf_mmap_open(struct vm_area_struct *vma)
+{
+ struct perf_event *event = vma->vm_file->private_data;
+
+ atomic_inc(&event->mmap_count);
+}
+
+static void perf_mmap_close(struct vm_area_struct *vma)
+{
+ struct perf_event *event = vma->vm_file->private_data;
+
+ WARN_ON_ONCE(event->ctx->parent_ctx);
+ if (atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) {
+ struct user_struct *user = current_user();
+
+ atomic_long_sub(event->data->nr_pages + 1, &user->locked_vm);
+ vma->vm_mm->locked_vm -= event->data->nr_locked;
+ perf_mmap_data_free(event);
+ mutex_unlock(&event->mmap_mutex);
+ }
+}
+
+static const struct vm_operations_struct perf_mmap_vmops = {
+ .open = perf_mmap_open,
+ .close = perf_mmap_close,
+ .fault = perf_mmap_fault,
+ .page_mkwrite = perf_mmap_fault,
+};
+
+static int perf_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct perf_event *event = file->private_data;
+ unsigned long user_locked, user_lock_limit;
+ struct user_struct *user = current_user();
+ unsigned long locked, lock_limit;
+ unsigned long vma_size;
+ unsigned long nr_pages;
+ long user_extra, extra;
+ int ret = 0;
+
+ if (!(vma->vm_flags & VM_SHARED))
+ return -EINVAL;
+
+ vma_size = vma->vm_end - vma->vm_start;
+ nr_pages = (vma_size / PAGE_SIZE) - 1;
+
+ /*
+ * If we have data pages ensure they're a power-of-two number, so we
+ * can do bitmasks instead of modulo.
+ */
+ if (nr_pages != 0 && !is_power_of_2(nr_pages))
+ return -EINVAL;
+
+ if (vma_size != PAGE_SIZE * (1 + nr_pages))
+ return -EINVAL;
+
+ if (vma->vm_pgoff != 0)
+ return -EINVAL;
+
+ WARN_ON_ONCE(event->ctx->parent_ctx);
+ mutex_lock(&event->mmap_mutex);
+ if (event->output) {
+ ret = -EINVAL;
+ goto unlock;
+ }
+
+ if (atomic_inc_not_zero(&event->mmap_count)) {
+ if (nr_pages != event->data->nr_pages)
+ ret = -EINVAL;
+ goto unlock;
+ }
+
+ user_extra = nr_pages + 1;
+ user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10);
+
+ /*
+ * Increase the limit linearly with more CPUs:
+ */
+ user_lock_limit *= num_online_cpus();
+
+ user_locked = atomic_long_read(&user->locked_vm) + user_extra;
+
+ extra = 0;
+ if (user_locked > user_lock_limit)
+ extra = user_locked - user_lock_limit;
+
+ lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
+ lock_limit >>= PAGE_SHIFT;
+ locked = vma->vm_mm->locked_vm + extra;
+
+ if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() &&
+ !capable(CAP_IPC_LOCK)) {
+ ret = -EPERM;
+ goto unlock;
+ }
+
+ WARN_ON(event->data);
+ ret = perf_mmap_data_alloc(event, nr_pages);
+ if (ret)
+ goto unlock;
+
+ atomic_set(&event->mmap_count, 1);
+ atomic_long_add(user_extra, &user->locked_vm);
+ vma->vm_mm->locked_vm += extra;
+ event->data->nr_locked = extra;
+ if (vma->vm_flags & VM_WRITE)
+ event->data->writable = 1;
+
+unlock:
+ mutex_unlock(&event->mmap_mutex);
+
+ vma->vm_flags |= VM_RESERVED;
+ vma->vm_ops = &perf_mmap_vmops;
+
+ return ret;
+}
+
+static int perf_fasync(int fd, struct file *filp, int on)
+{
+ struct inode *inode = filp->f_path.dentry->d_inode;
+ struct perf_event *event = filp->private_data;
+ int retval;
+
+ mutex_lock(&inode->i_mutex);
+ retval = fasync_helper(fd, filp, on, &event->fasync);
+ mutex_unlock(&inode->i_mutex);
+
+ if (retval < 0)
+ return retval;
+
+ return 0;
+}
+
+static const struct file_operations perf_fops = {
+ .release = perf_release,
+ .read = perf_read,
+ .poll = perf_poll,
+ .unlocked_ioctl = perf_ioctl,
+ .compat_ioctl = perf_ioctl,
+ .mmap = perf_mmap,
+ .fasync = perf_fasync,
+};
+
+/*
+ * Perf event wakeup
+ *
+ * If there's data, ensure we set the poll() state and publish everything
+ * to user-space before waking everybody up.
+ */
+
+void perf_event_wakeup(struct perf_event *event)
+{
+ wake_up_all(&event->waitq);
+
+ if (event->pending_kill) {
+ kill_fasync(&event->fasync, SIGIO, event->pending_kill);
+ event->pending_kill = 0;
+ }
+}
+
+/*
+ * Pending wakeups
+ *
+ * Handle the case where we need to wakeup up from NMI (or rq->lock) context.
+ *
+ * The NMI bit means we cannot possibly take locks. Therefore, maintain a
+ * single linked list and use cmpxchg() to add entries lockless.
+ */
+
+static void perf_pending_event(struct perf_pending_entry *entry)
+{
+ struct perf_event *event = container_of(entry,
+ struct perf_event, pending);
+
+ if (event->pending_disable) {
+ event->pending_disable = 0;
+ __perf_event_disable(event);
+ }
+
+ if (event->pending_wakeup) {
+ event->pending_wakeup = 0;
+ perf_event_wakeup(event);
+ }
+}
+
+#define PENDING_TAIL ((struct perf_pending_entry *)-1UL)
+
+static DEFINE_PER_CPU(struct perf_pending_entry *, perf_pending_head) = {
+ PENDING_TAIL,
+};
+
+static void perf_pending_queue(struct perf_pending_entry *entry,
+ void (*func)(struct perf_pending_entry *))
+{
+ struct perf_pending_entry **head;
+
+ if (cmpxchg(&entry->next, NULL, PENDING_TAIL) != NULL)
+ return;
+
+ entry->func = func;
+
+ head = &get_cpu_var(perf_pending_head);
+
+ do {
+ entry->next = *head;
+ } while (cmpxchg(head, entry->next, entry) != entry->next);
+
+ set_perf_event_pending();
+
+ put_cpu_var(perf_pending_head);
+}
+
+static int __perf_pending_run(void)
+{
+ struct perf_pending_entry *list;
+ int nr = 0;
+
+ list = xchg(&__get_cpu_var(perf_pending_head), PENDING_TAIL);
+ while (list != PENDING_TAIL) {
+ void (*func)(struct perf_pending_entry *);
+ struct perf_pending_entry *entry = list;
+
+ list = list->next;
+
+ func = entry->func;
+ entry->next = NULL;
+ /*
+ * Ensure we observe the unqueue before we issue the wakeup,
+ * so that we won't be waiting forever.
+ * -- see perf_not_pending().
+ */
+ smp_wmb();
+
+ func(entry);
+ nr++;
+ }
+
+ return nr;
+}
+
+static inline int perf_not_pending(struct perf_event *event)
+{
+ /*
+ * If we flush on whatever cpu we run, there is a chance we don't
+ * need to wait.
+ */
+ get_cpu();
+ __perf_pending_run();
+ put_cpu();
+
+ /*
+ * Ensure we see the proper queue state before going to sleep
+ * so that we do not miss the wakeup. -- see perf_pending_handle()
+ */
+ smp_rmb();
+ return event->pending.next == NULL;
+}
+
+static void perf_pending_sync(struct perf_event *event)
+{
+ wait_event(event->waitq, perf_not_pending(event));
+}
+
+void perf_event_do_pending(void)
+{
+ __perf_pending_run();
+}
+
+/*
+ * Callchain support -- arch specific
+ */
+
+__weak struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
+{
+ return NULL;
+}
+
+/*
+ * Output
+ */
+static bool perf_output_space(struct perf_mmap_data *data, unsigned long tail,
+ unsigned long offset, unsigned long head)
+{
+ unsigned long mask;
+
+ if (!data->writable)
+ return true;
+
+ mask = (data->nr_pages << PAGE_SHIFT) - 1;
+
+ offset = (offset - tail) & mask;
+ head = (head - tail) & mask;
+
+ if ((int)(head - offset) < 0)
+ return false;
+
+ return true;
+}
+
+static void perf_output_wakeup(struct perf_output_handle *handle)
+{
+ atomic_set(&handle->data->poll, POLL_IN);
+
+ if (handle->nmi) {
+ handle->event->pending_wakeup = 1;
+ perf_pending_queue(&handle->event->pending,
+ perf_pending_event);
+ } else
+ perf_event_wakeup(handle->event);
+}
+
+/*
+ * Curious locking construct.
+ *
+ * We need to ensure a later event_id doesn't publish a head when a former
+ * event_id isn't done writing. However since we need to deal with NMIs we
+ * cannot fully serialize things.
+ *
+ * What we do is serialize between CPUs so we only have to deal with NMI
+ * nesting on a single CPU.
+ *
+ * We only publish the head (and generate a wakeup) when the outer-most
+ * event_id completes.
+ */
+static void perf_output_lock(struct perf_output_handle *handle)
+{
+ struct perf_mmap_data *data = handle->data;
+ int cpu;
+
+ handle->locked = 0;
+
+ local_irq_save(handle->flags);
+ cpu = smp_processor_id();
+
+ if (in_nmi() && atomic_read(&data->lock) == cpu)
+ return;
+
+ while (atomic_cmpxchg(&data->lock, -1, cpu) != -1)
+ cpu_relax();
+
+ handle->locked = 1;
+}
+
+static void perf_output_unlock(struct perf_output_handle *handle)
+{
+ struct perf_mmap_data *data = handle->data;
+ unsigned long head;
+ int cpu;
+
+ data->done_head = data->head;
+
+ if (!handle->locked)
+ goto out;
+
+again:
+ /*
+ * The xchg implies a full barrier that ensures all writes are done
+ * before we publish the new head, matched by a rmb() in userspace when
+ * reading this position.
+ */
+ while ((head = atomic_long_xchg(&data->done_head, 0)))
+ data->user_page->data_head = head;
+
+ /*
+ * NMI can happen here, which means we can miss a done_head update.
+ */
+
+ cpu = atomic_xchg(&data->lock, -1);
+ WARN_ON_ONCE(cpu != smp_processor_id());
+
+ /*
+ * Therefore we have to validate we did not indeed do so.
+ */
+ if (unlikely(atomic_long_read(&data->done_head))) {
+ /*
+ * Since we had it locked, we can lock it again.
+ */
+ while (atomic_cmpxchg(&data->lock, -1, cpu) != -1)
+ cpu_relax();
+
+ goto again;
+ }
+
+ if (atomic_xchg(&data->wakeup, 0))
+ perf_output_wakeup(handle);
+out:
+ local_irq_restore(handle->flags);
+}
+
+void perf_output_copy(struct perf_output_handle *handle,
+ const void *buf, unsigned int len)
+{
+ unsigned int pages_mask;
+ unsigned int offset;
+ unsigned int size;
+ void **pages;
+
+ offset = handle->offset;
+ pages_mask = handle->data->nr_pages - 1;
+ pages = handle->data->data_pages;
+
+ do {
+ unsigned int page_offset;
+ int nr;
+
+ nr = (offset >> PAGE_SHIFT) & pages_mask;
+ page_offset = offset & (PAGE_SIZE - 1);
+ size = min_t(unsigned int, PAGE_SIZE - page_offset, len);
+
+ memcpy(pages[nr] + page_offset, buf, size);
+
+ len -= size;
+ buf += size;
+ offset += size;
+ } while (len);
+
+ handle->offset = offset;
+
+ /*
+ * Check we didn't copy past our reservation window, taking the
+ * possible unsigned int wrap into account.
+ */
+ WARN_ON_ONCE(((long)(handle->head - handle->offset)) < 0);
+}
+
+int perf_output_begin(struct perf_output_handle *handle,
+ struct perf_event *event, unsigned int size,
+ int nmi, int sample)
+{
+ struct perf_event *output_event;
+ struct perf_mmap_data *data;
+ unsigned long tail, offset, head;
+ int have_lost;
+ struct {
+ struct perf_event_header header;
+ u64 id;
+ u64 lost;
+ } lost_event;
+
+ rcu_read_lock();
+ /*
+ * For inherited events we send all the output towards the parent.
+ */
+ if (event->parent)
+ event = event->parent;
+
+ output_event = rcu_dereference(event->output);
+ if (output_event)
+ event = output_event;
+
+ data = rcu_dereference(event->data);
+ if (!data)
+ goto out;
+
+ handle->data = data;
+ handle->event = event;
+ handle->nmi = nmi;
+ handle->sample = sample;
+
+ if (!data->nr_pages)
+ goto fail;
+
+ have_lost = atomic_read(&data->lost);
+ if (have_lost)
+ size += sizeof(lost_event);
+
+ perf_output_lock(handle);
+
+ do {
+ /*
+ * Userspace could choose to issue a mb() before updating the
+ * tail pointer. So that all reads will be completed before the
+ * write is issued.
+ */
+ tail = ACCESS_ONCE(data->user_page->data_tail);
+ smp_rmb();
+ offset = head = atomic_long_read(&data->head);
+ head += size;
+ if (unlikely(!perf_output_space(data, tail, offset, head)))
+ goto fail;
+ } while (atomic_long_cmpxchg(&data->head, offset, head) != offset);
+
+ handle->offset = offset;
+ handle->head = head;
+
+ if (head - tail > data->watermark)
+ atomic_set(&data->wakeup, 1);
+
+ if (have_lost) {
+ lost_event.header.type = PERF_RECORD_LOST;
+ lost_event.header.misc = 0;
+ lost_event.header.size = sizeof(lost_event);
+ lost_event.id = event->id;
+ lost_event.lost = atomic_xchg(&data->lost, 0);
+
+ perf_output_put(handle, lost_event);
+ }
+
+ return 0;
+
+fail:
+ atomic_inc(&data->lost);
+ perf_output_unlock(handle);
+out:
+ rcu_read_unlock();
+
+ return -ENOSPC;
+}
+
+void perf_output_end(struct perf_output_handle *handle)
+{
+ struct perf_event *event = handle->event;
+ struct perf_mmap_data *data = handle->data;
+
+ int wakeup_events = event->attr.wakeup_events;
+
+ if (handle->sample && wakeup_events) {
+ int events = atomic_inc_return(&data->events);
+ if (events >= wakeup_events) {
+ atomic_sub(wakeup_events, &data->events);
+ atomic_set(&data->wakeup, 1);
+ }
+ }
+
+ perf_output_unlock(handle);
+ rcu_read_unlock();
+}
+
+static u32 perf_event_pid(struct perf_event *event, struct task_struct *p)
+{
+ /*
+ * only top level events have the pid namespace they were created in
+ */
+ if (event->parent)
+ event = event->parent;
+
+ return task_tgid_nr_ns(p, event->ns);
+}
+
+static u32 perf_event_tid(struct perf_event *event, struct task_struct *p)
+{
+ /*
+ * only top level events have the pid namespace they were created in
+ */
+ if (event->parent)
+ event = event->parent;
+
+ return task_pid_nr_ns(p, event->ns);
+}
+
+static void perf_output_read_one(struct perf_output_handle *handle,
+ struct perf_event *event)
+{
+ u64 read_format = event->attr.read_format;
+ u64 values[4];
+ int n = 0;
+
+ values[n++] = atomic64_read(&event->count);
+ if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
+ values[n++] = event->total_time_enabled +
+ atomic64_read(&event->child_total_time_enabled);
+ }
+ if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
+ values[n++] = event->total_time_running +
+ atomic64_read(&event->child_total_time_running);
+ }
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_event_id(event);
+
+ perf_output_copy(handle, values, n * sizeof(u64));
+}
+
+/*
+ * XXX PERF_FORMAT_GROUP vs inherited events seems difficult.
+ */
+static void perf_output_read_group(struct perf_output_handle *handle,
+ struct perf_event *event)
+{
+ struct perf_event *leader = event->group_leader, *sub;
+ u64 read_format = event->attr.read_format;
+ u64 values[5];
+ int n = 0;
+
+ values[n++] = 1 + leader->nr_siblings;
+
+ if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+ values[n++] = leader->total_time_enabled;
+
+ if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+ values[n++] = leader->total_time_running;
+
+ if (leader != event)
+ leader->pmu->read(leader);
+
+ values[n++] = atomic64_read(&leader->count);
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_event_id(leader);
+
+ perf_output_copy(handle, values, n * sizeof(u64));
+
+ list_for_each_entry(sub, &leader->sibling_list, group_entry) {
+ n = 0;
+
+ if (sub != event)
+ sub->pmu->read(sub);
+
+ values[n++] = atomic64_read(&sub->count);
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_event_id(sub);
+
+ perf_output_copy(handle, values, n * sizeof(u64));
+ }
+}
+
+static void perf_output_read(struct perf_output_handle *handle,
+ struct perf_event *event)
+{
+ if (event->attr.read_format & PERF_FORMAT_GROUP)
+ perf_output_read_group(handle, event);
+ else
+ perf_output_read_one(handle, event);
+}
+
+void perf_output_sample(struct perf_output_handle *handle,
+ struct perf_event_header *header,
+ struct perf_sample_data *data,
+ struct perf_event *event)
+{
+ u64 sample_type = data->type;
+
+ perf_output_put(handle, *header);
+
+ if (sample_type & PERF_SAMPLE_IP)
+ perf_output_put(handle, data->ip);
+
+ if (sample_type & PERF_SAMPLE_TID)
+ perf_output_put(handle, data->tid_entry);
+
+ if (sample_type & PERF_SAMPLE_TIME)
+ perf_output_put(handle, data->time);
+
+ if (sample_type & PERF_SAMPLE_ADDR)
+ perf_output_put(handle, data->addr);
+
+ if (sample_type & PERF_SAMPLE_ID)
+ perf_output_put(handle, data->id);
+
+ if (sample_type & PERF_SAMPLE_STREAM_ID)
+ perf_output_put(handle, data->stream_id);
+
+ if (sample_type & PERF_SAMPLE_CPU)
+ perf_output_put(handle, data->cpu_entry);
+
+ if (sample_type & PERF_SAMPLE_PERIOD)
+ perf_output_put(handle, data->period);
+
+ if (sample_type & PERF_SAMPLE_READ)
+ perf_output_read(handle, event);
+
+ if (sample_type & PERF_SAMPLE_CALLCHAIN) {
+ if (data->callchain) {
+ int size = 1;
+
+ if (data->callchain)
+ size += data->callchain->nr;
+
+ size *= sizeof(u64);
+
+ perf_output_copy(handle, data->callchain, size);
+ } else {
+ u64 nr = 0;
+ perf_output_put(handle, nr);
+ }
+ }
+
+ if (sample_type & PERF_SAMPLE_RAW) {
+ if (data->raw) {
+ perf_output_put(handle, data->raw->size);
+ perf_output_copy(handle, data->raw->data,
+ data->raw->size);
+ } else {
+ struct {
+ u32 size;
+ u32 data;
+ } raw = {
+ .size = sizeof(u32),
+ .data = 0,
+ };
+ perf_output_put(handle, raw);
+ }
+ }
+}
+
+void perf_prepare_sample(struct perf_event_header *header,
+ struct perf_sample_data *data,
+ struct perf_event *event,
+ struct pt_regs *regs)
+{
+ u64 sample_type = event->attr.sample_type;
+
+ data->type = sample_type;
+
+ header->type = PERF_RECORD_SAMPLE;
+ header->size = sizeof(*header);
+
+ header->misc = 0;
+ header->misc |= perf_misc_flags(regs);
+
+ if (sample_type & PERF_SAMPLE_IP) {
+ data->ip = perf_instruction_pointer(regs);
+
+ header->size += sizeof(data->ip);
+ }
+
+ if (sample_type & PERF_SAMPLE_TID) {
+ /* namespace issues */
+ data->tid_entry.pid = perf_event_pid(event, current);
+ data->tid_entry.tid = perf_event_tid(event, current);
+
+ header->size += sizeof(data->tid_entry);
+ }
+
+ if (sample_type & PERF_SAMPLE_TIME) {
+ data->time = perf_clock();
+
+ header->size += sizeof(data->time);
+ }
+
+ if (sample_type & PERF_SAMPLE_ADDR)
+ header->size += sizeof(data->addr);
+
+ if (sample_type & PERF_SAMPLE_ID) {
+ data->id = primary_event_id(event);
+
+ header->size += sizeof(data->id);
+ }
+
+ if (sample_type & PERF_SAMPLE_STREAM_ID) {
+ data->stream_id = event->id;
+
+ header->size += sizeof(data->stream_id);
+ }
+
+ if (sample_type & PERF_SAMPLE_CPU) {
+ data->cpu_entry.cpu = raw_smp_processor_id();
+ data->cpu_entry.reserved = 0;
+
+ header->size += sizeof(data->cpu_entry);
+ }
+
+ if (sample_type & PERF_SAMPLE_PERIOD)
+ header->size += sizeof(data->period);
+
+ if (sample_type & PERF_SAMPLE_READ)
+ header->size += perf_event_read_size(event);
+
+ if (sample_type & PERF_SAMPLE_CALLCHAIN) {
+ int size = 1;
+
+ data->callchain = perf_callchain(regs);
+
+ if (data->callchain)
+ size += data->callchain->nr;
+
+ header->size += size * sizeof(u64);
+ }
+
+ if (sample_type & PERF_SAMPLE_RAW) {
+ int size = sizeof(u32);
+
+ if (data->raw)
+ size += data->raw->size;
+ else
+ size += sizeof(u32);
+
+ WARN_ON_ONCE(size & (sizeof(u64)-1));
+ header->size += size;
+ }
+}
+
+static void perf_event_output(struct perf_event *event, int nmi,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ struct perf_output_handle handle;
+ struct perf_event_header header;
+
+ perf_prepare_sample(&header, data, event, regs);
+
+ if (perf_output_begin(&handle, event, header.size, nmi, 1))
+ return;
+
+ perf_output_sample(&handle, &header, data, event);
+
+ perf_output_end(&handle);
+}
+
+/*
+ * read event_id
+ */
+
+struct perf_read_event {
+ struct perf_event_header header;
+
+ u32 pid;
+ u32 tid;
+};
+
+static void
+perf_event_read_event(struct perf_event *event,
+ struct task_struct *task)
+{
+ struct perf_output_handle handle;
+ struct perf_read_event read_event = {
+ .header = {
+ .type = PERF_RECORD_READ,
+ .misc = 0,
+ .size = sizeof(read_event) + perf_event_read_size(event),
+ },
+ .pid = perf_event_pid(event, task),
+ .tid = perf_event_tid(event, task),
+ };
+ int ret;
+
+ ret = perf_output_begin(&handle, event, read_event.header.size, 0, 0);
+ if (ret)
+ return;
+
+ perf_output_put(&handle, read_event);
+ perf_output_read(&handle, event);
+
+ perf_output_end(&handle);
+}
+
+/*
+ * task tracking -- fork/exit
+ *
+ * enabled by: attr.comm | attr.mmap | attr.task
+ */
+
+struct perf_task_event {
+ struct task_struct *task;
+ struct perf_event_context *task_ctx;
+
+ struct {
+ struct perf_event_header header;
+
+ u32 pid;
+ u32 ppid;
+ u32 tid;
+ u32 ptid;
+ u64 time;
+ } event_id;
+};
+
+static void perf_event_task_output(struct perf_event *event,
+ struct perf_task_event *task_event)
+{
+ struct perf_output_handle handle;
+ int size;
+ struct task_struct *task = task_event->task;
+ int ret;
+
+ size = task_event->event_id.header.size;
+ ret = perf_output_begin(&handle, event, size, 0, 0);
+
+ if (ret)
+ return;
+
+ task_event->event_id.pid = perf_event_pid(event, task);
+ task_event->event_id.ppid = perf_event_pid(event, current);
+
+ task_event->event_id.tid = perf_event_tid(event, task);
+ task_event->event_id.ptid = perf_event_tid(event, current);
+
+ task_event->event_id.time = perf_clock();
+
+ perf_output_put(&handle, task_event->event_id);
+
+ perf_output_end(&handle);
+}
+
+static int perf_event_task_match(struct perf_event *event)
+{
+ if (event->attr.comm || event->attr.mmap || event->attr.task)
+ return 1;
+
+ return 0;
+}
+
+static void perf_event_task_ctx(struct perf_event_context *ctx,
+ struct perf_task_event *task_event)
+{
+ struct perf_event *event;
+
+ if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
+ return;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
+ if (perf_event_task_match(event))
+ perf_event_task_output(event, task_event);
+ }
+ rcu_read_unlock();
+}
+
+static void perf_event_task_event(struct perf_task_event *task_event)
+{
+ struct perf_cpu_context *cpuctx;
+ struct perf_event_context *ctx = task_event->task_ctx;
+
+ cpuctx = &get_cpu_var(perf_cpu_context);
+ perf_event_task_ctx(&cpuctx->ctx, task_event);
+ put_cpu_var(perf_cpu_context);
+
+ rcu_read_lock();
+ if (!ctx)
+ ctx = rcu_dereference(task_event->task->perf_event_ctxp);
+ if (ctx)
+ perf_event_task_ctx(ctx, task_event);
+ rcu_read_unlock();
+}
+
+static void perf_event_task(struct task_struct *task,
+ struct perf_event_context *task_ctx,
+ int new)
+{
+ struct perf_task_event task_event;
+
+ if (!atomic_read(&nr_comm_events) &&
+ !atomic_read(&nr_mmap_events) &&
+ !atomic_read(&nr_task_events))
+ return;
+
+ task_event = (struct perf_task_event){
+ .task = task,
+ .task_ctx = task_ctx,
+ .event_id = {
+ .header = {
+ .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT,
+ .misc = 0,
+ .size = sizeof(task_event.event_id),
+ },
+ /* .pid */
+ /* .ppid */
+ /* .tid */
+ /* .ptid */
+ },
+ };
+
+ perf_event_task_event(&task_event);
+}
+
+void perf_event_fork(struct task_struct *task)
+{
+ perf_event_task(task, NULL, 1);
+}
+
+/*
+ * comm tracking
+ */
+
+struct perf_comm_event {
+ struct task_struct *task;
+ char *comm;
+ int comm_size;
+
+ struct {
+ struct perf_event_header header;
+
+ u32 pid;
+ u32 tid;
+ } event_id;
+};
+
+static void perf_event_comm_output(struct perf_event *event,
+ struct perf_comm_event *comm_event)
+{
+ struct perf_output_handle handle;
+ int size = comm_event->event_id.header.size;
+ int ret = perf_output_begin(&handle, event, size, 0, 0);
+
+ if (ret)
+ return;
+
+ comm_event->event_id.pid = perf_event_pid(event, comm_event->task);
+ comm_event->event_id.tid = perf_event_tid(event, comm_event->task);
+
+ perf_output_put(&handle, comm_event->event_id);
+ perf_output_copy(&handle, comm_event->comm,
+ comm_event->comm_size);
+ perf_output_end(&handle);
+}
+
+static int perf_event_comm_match(struct perf_event *event)
+{
+ if (event->attr.comm)
+ return 1;
+
+ return 0;
+}
+
+static void perf_event_comm_ctx(struct perf_event_context *ctx,
+ struct perf_comm_event *comm_event)
+{
+ struct perf_event *event;
+
+ if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
+ return;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
+ if (perf_event_comm_match(event))
+ perf_event_comm_output(event, comm_event);
+ }
+ rcu_read_unlock();
+}
+
+static void perf_event_comm_event(struct perf_comm_event *comm_event)
+{
+ struct perf_cpu_context *cpuctx;
+ struct perf_event_context *ctx;
+ unsigned int size;
+ char comm[TASK_COMM_LEN];
+
+ memset(comm, 0, sizeof(comm));
+ strncpy(comm, comm_event->task->comm, sizeof(comm));
+ size = ALIGN(strlen(comm)+1, sizeof(u64));
+
+ comm_event->comm = comm;
+ comm_event->comm_size = size;
+
+ comm_event->event_id.header.size = sizeof(comm_event->event_id) + size;
+
+ cpuctx = &get_cpu_var(perf_cpu_context);
+ perf_event_comm_ctx(&cpuctx->ctx, comm_event);
+ put_cpu_var(perf_cpu_context);
+
+ rcu_read_lock();
+ /*
+ * doesn't really matter which of the child contexts the
+ * events ends up in.
+ */
+ ctx = rcu_dereference(current->perf_event_ctxp);
+ if (ctx)
+ perf_event_comm_ctx(ctx, comm_event);
+ rcu_read_unlock();
+}
+
+void perf_event_comm(struct task_struct *task)
+{
+ struct perf_comm_event comm_event;
+
+ if (task->perf_event_ctxp)
+ perf_event_enable_on_exec(task);
+
+ if (!atomic_read(&nr_comm_events))
+ return;
+
+ comm_event = (struct perf_comm_event){
+ .task = task,
+ /* .comm */
+ /* .comm_size */
+ .event_id = {
+ .header = {
+ .type = PERF_RECORD_COMM,
+ .misc = 0,
+ /* .size */
+ },
+ /* .pid */
+ /* .tid */
+ },
+ };
+
+ perf_event_comm_event(&comm_event);
+}
+
+/*
+ * mmap tracking
+ */
+
+struct perf_mmap_event {
+ struct vm_area_struct *vma;
+
+ const char *file_name;
+ int file_size;
+
+ struct {
+ struct perf_event_header header;
+
+ u32 pid;
+ u32 tid;
+ u64 start;
+ u64 len;
+ u64 pgoff;
+ } event_id;
+};
+
+static void perf_event_mmap_output(struct perf_event *event,
+ struct perf_mmap_event *mmap_event)
+{
+ struct perf_output_handle handle;
+ int size = mmap_event->event_id.header.size;
+ int ret = perf_output_begin(&handle, event, size, 0, 0);
+
+ if (ret)
+ return;
+
+ mmap_event->event_id.pid = perf_event_pid(event, current);
+ mmap_event->event_id.tid = perf_event_tid(event, current);
+
+ perf_output_put(&handle, mmap_event->event_id);
+ perf_output_copy(&handle, mmap_event->file_name,
+ mmap_event->file_size);
+ perf_output_end(&handle);
+}
+
+static int perf_event_mmap_match(struct perf_event *event,
+ struct perf_mmap_event *mmap_event)
+{
+ if (event->attr.mmap)
+ return 1;
+
+ return 0;
+}
+
+static void perf_event_mmap_ctx(struct perf_event_context *ctx,
+ struct perf_mmap_event *mmap_event)
+{
+ struct perf_event *event;
+
+ if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
+ return;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
+ if (perf_event_mmap_match(event, mmap_event))
+ perf_event_mmap_output(event, mmap_event);
+ }
+ rcu_read_unlock();
+}
+
+static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
+{
+ struct perf_cpu_context *cpuctx;
+ struct perf_event_context *ctx;
+ struct vm_area_struct *vma = mmap_event->vma;
+ struct file *file = vma->vm_file;
+ unsigned int size;
+ char tmp[16];
+ char *buf = NULL;
+ const char *name;
+
+ memset(tmp, 0, sizeof(tmp));
+
+ if (file) {
+ /*
+ * d_path works from the end of the buffer backwards, so we
+ * need to add enough zero bytes after the string to handle
+ * the 64bit alignment we do later.
+ */
+ buf = kzalloc(PATH_MAX + sizeof(u64), GFP_KERNEL);
+ if (!buf) {
+ name = strncpy(tmp, "//enomem", sizeof(tmp));
+ goto got_name;
+ }
+ name = d_path(&file->f_path, buf, PATH_MAX);
+ if (IS_ERR(name)) {
+ name = strncpy(tmp, "//toolong", sizeof(tmp));
+ goto got_name;
+ }
+ } else {
+ if (arch_vma_name(mmap_event->vma)) {
+ name = strncpy(tmp, arch_vma_name(mmap_event->vma),
+ sizeof(tmp));
+ goto got_name;
+ }
+
+ if (!vma->vm_mm) {
+ name = strncpy(tmp, "[vdso]", sizeof(tmp));
+ goto got_name;
+ }
+
+ name = strncpy(tmp, "//anon", sizeof(tmp));
+ goto got_name;
+ }
+
+got_name:
+ size = ALIGN(strlen(name)+1, sizeof(u64));
+
+ mmap_event->file_name = name;
+ mmap_event->file_size = size;
+
+ mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size;
+
+ cpuctx = &get_cpu_var(perf_cpu_context);
+ perf_event_mmap_ctx(&cpuctx->ctx, mmap_event);
+ put_cpu_var(perf_cpu_context);
+
+ rcu_read_lock();
+ /*
+ * doesn't really matter which of the child contexts the
+ * events ends up in.
+ */
+ ctx = rcu_dereference(current->perf_event_ctxp);
+ if (ctx)
+ perf_event_mmap_ctx(ctx, mmap_event);
+ rcu_read_unlock();
+
+ kfree(buf);
+}
+
+void __perf_event_mmap(struct vm_area_struct *vma)
+{
+ struct perf_mmap_event mmap_event;
+
+ if (!atomic_read(&nr_mmap_events))
+ return;
+
+ mmap_event = (struct perf_mmap_event){
+ .vma = vma,
+ /* .file_name */
+ /* .file_size */
+ .event_id = {
+ .header = {
+ .type = PERF_RECORD_MMAP,
+ .misc = 0,
+ /* .size */
+ },
+ /* .pid */
+ /* .tid */
+ .start = vma->vm_start,
+ .len = vma->vm_end - vma->vm_start,
+ .pgoff = vma->vm_pgoff,
+ },
+ };
+
+ perf_event_mmap_event(&mmap_event);
+}
+
+/*
+ * IRQ throttle logging
+ */
+
+static void perf_log_throttle(struct perf_event *event, int enable)
+{
+ struct perf_output_handle handle;
+ int ret;
+
+ struct {
+ struct perf_event_header header;
+ u64 time;
+ u64 id;
+ u64 stream_id;
+ } throttle_event = {
+ .header = {
+ .type = PERF_RECORD_THROTTLE,
+ .misc = 0,
+ .size = sizeof(throttle_event),
+ },
+ .time = perf_clock(),
+ .id = primary_event_id(event),
+ .stream_id = event->id,
+ };
+
+ if (enable)
+ throttle_event.header.type = PERF_RECORD_UNTHROTTLE;
+
+ ret = perf_output_begin(&handle, event, sizeof(throttle_event), 1, 0);
+ if (ret)
+ return;
+
+ perf_output_put(&handle, throttle_event);
+ perf_output_end(&handle);
+}
+
+/*
+ * Generic event overflow handling, sampling.
+ */
+
+static int __perf_event_overflow(struct perf_event *event, int nmi,
+ int throttle, struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ int events = atomic_read(&event->event_limit);
+ struct hw_perf_event *hwc = &event->hw;
+ int ret = 0;
+
+ throttle = (throttle && event->pmu->unthrottle != NULL);
+
+ if (!throttle) {
+ hwc->interrupts++;
+ } else {
+ if (hwc->interrupts != MAX_INTERRUPTS) {
+ hwc->interrupts++;
+ if (HZ * hwc->interrupts >
+ (u64)sysctl_perf_event_sample_rate) {
+ hwc->interrupts = MAX_INTERRUPTS;
+ perf_log_throttle(event, 0);
+ ret = 1;
+ }
+ } else {
+ /*
+ * Keep re-disabling events even though on the previous
+ * pass we disabled it - just in case we raced with a
+ * sched-in and the event got enabled again:
+ */
+ ret = 1;
+ }
+ }
+
+ if (event->attr.freq) {
+ u64 now = perf_clock();
+ s64 delta = now - hwc->freq_stamp;
+
+ hwc->freq_stamp = now;
+
+ if (delta > 0 && delta < TICK_NSEC)
+ perf_adjust_period(event, NSEC_PER_SEC / (int)delta);
+ }
+
+ /*
+ * XXX event_limit might not quite work as expected on inherited
+ * events
+ */
+
+ event->pending_kill = POLL_IN;
+ if (events && atomic_dec_and_test(&event->event_limit)) {
+ ret = 1;
+ event->pending_kill = POLL_HUP;
+ if (nmi) {
+ event->pending_disable = 1;
+ perf_pending_queue(&event->pending,
+ perf_pending_event);
+ } else
+ perf_event_disable(event);
+ }
+
+ perf_event_output(event, nmi, data, regs);
+ return ret;
+}
+
+int perf_event_overflow(struct perf_event *event, int nmi,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ return __perf_event_overflow(event, nmi, 1, data, regs);
+}
+
+/*
+ * Generic software event infrastructure
+ */
+
+/*
+ * We directly increment event->count and keep a second value in
+ * event->hw.period_left to count intervals. This period event
+ * is kept in the range [-sample_period, 0] so that we can use the
+ * sign as trigger.
+ */
+
+static u64 perf_swevent_set_period(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ u64 period = hwc->last_period;
+ u64 nr, offset;
+ s64 old, val;
+
+ hwc->last_period = hwc->sample_period;
+
+again:
+ old = val = atomic64_read(&hwc->period_left);
+ if (val < 0)
+ return 0;
+
+ nr = div64_u64(period + val, period);
+ offset = nr * period;
+ val -= offset;
+ if (atomic64_cmpxchg(&hwc->period_left, old, val) != old)
+ goto again;
+
+ return nr;
+}
+
+static void perf_swevent_overflow(struct perf_event *event,
+ int nmi, struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ int throttle = 0;
+ u64 overflow;
+
+ data->period = event->hw.last_period;
+ overflow = perf_swevent_set_period(event);
+
+ if (hwc->interrupts == MAX_INTERRUPTS)
+ return;
+
+ for (; overflow; overflow--) {
+ if (__perf_event_overflow(event, nmi, throttle,
+ data, regs)) {
+ /*
+ * We inhibit the overflow from happening when
+ * hwc->interrupts == MAX_INTERRUPTS.
+ */
+ break;
+ }
+ throttle = 1;
+ }
+}
+
+static void perf_swevent_unthrottle(struct perf_event *event)
+{
+ /*
+ * Nothing to do, we already reset hwc->interrupts.
+ */
+}
+
+static void perf_swevent_add(struct perf_event *event, u64 nr,
+ int nmi, struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ struct hw_perf_event *hwc = &event->hw;
+
+ atomic64_add(nr, &event->count);
+
+ if (!hwc->sample_period)
+ return;
+
+ if (!regs)
+ return;
+
+ if (!atomic64_add_negative(nr, &hwc->period_left))
+ perf_swevent_overflow(event, nmi, data, regs);
+}
+
+static int perf_swevent_is_counting(struct perf_event *event)
+{
+ /*
+ * The event is active, we're good!
+ */
+ if (event->state == PERF_EVENT_STATE_ACTIVE)
+ return 1;
+
+ /*
+ * The event is off/error, not counting.
+ */
+ if (event->state != PERF_EVENT_STATE_INACTIVE)
+ return 0;
+
+ /*
+ * The event is inactive, if the context is active
+ * we're part of a group that didn't make it on the 'pmu',
+ * not counting.
+ */
+ if (event->ctx->is_active)
+ return 0;
+
+ /*
+ * We're inactive and the context is too, this means the
+ * task is scheduled out, we're counting events that happen
+ * to us, like migration events.
+ */
+ return 1;
+}
+
+static int perf_swevent_match(struct perf_event *event,
+ enum perf_type_id type,
+ u32 event_id, struct pt_regs *regs)
+{
+ if (!perf_swevent_is_counting(event))
+ return 0;
+
+ if (event->attr.type != type)
+ return 0;
+ if (event->attr.config != event_id)
+ return 0;
+
+ if (regs) {
+ if (event->attr.exclude_user && user_mode(regs))
+ return 0;
+
+ if (event->attr.exclude_kernel && !user_mode(regs))
+ return 0;
+ }
+
+ return 1;
+}
+
+static void perf_swevent_ctx_event(struct perf_event_context *ctx,
+ enum perf_type_id type,
+ u32 event_id, u64 nr, int nmi,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ struct perf_event *event;
+
+ if (system_state != SYSTEM_RUNNING || list_empty(&ctx->event_list))
+ return;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
+ if (perf_swevent_match(event, type, event_id, regs))
+ perf_swevent_add(event, nr, nmi, data, regs);
+ }
+ rcu_read_unlock();
+}
+
+static int *perf_swevent_recursion_context(struct perf_cpu_context *cpuctx)
+{
+ if (in_nmi())
+ return &cpuctx->recursion[3];
+
+ if (in_irq())
+ return &cpuctx->recursion[2];
+
+ if (in_softirq())
+ return &cpuctx->recursion[1];
+
+ return &cpuctx->recursion[0];
+}
+
+static void do_perf_sw_event(enum perf_type_id type, u32 event_id,
+ u64 nr, int nmi,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ struct perf_cpu_context *cpuctx = &get_cpu_var(perf_cpu_context);
+ int *recursion = perf_swevent_recursion_context(cpuctx);
+ struct perf_event_context *ctx;
+
+ if (*recursion)
+ goto out;
+
+ (*recursion)++;
+ barrier();
+
+ perf_swevent_ctx_event(&cpuctx->ctx, type, event_id,
+ nr, nmi, data, regs);
+ rcu_read_lock();
+ /*
+ * doesn't really matter which of the child contexts the
+ * events ends up in.
+ */
+ ctx = rcu_dereference(current->perf_event_ctxp);
+ if (ctx)
+ perf_swevent_ctx_event(ctx, type, event_id, nr, nmi, data, regs);
+ rcu_read_unlock();
+
+ barrier();
+ (*recursion)--;
+
+out:
+ put_cpu_var(perf_cpu_context);
+}
+
+void __perf_sw_event(u32 event_id, u64 nr, int nmi,
+ struct pt_regs *regs, u64 addr)
+{
+ struct perf_sample_data data = {
+ .addr = addr,
+ };
+
+ do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, nmi,
+ &data, regs);
+}
+
+static void perf_swevent_read(struct perf_event *event)
+{
+}
+
+static int perf_swevent_enable(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+
+ if (hwc->sample_period) {
+ hwc->last_period = hwc->sample_period;
+ perf_swevent_set_period(event);
+ }
+ return 0;
+}
+
+static void perf_swevent_disable(struct perf_event *event)
+{
+}
+
+static const struct pmu perf_ops_generic = {
+ .enable = perf_swevent_enable,
+ .disable = perf_swevent_disable,
+ .read = perf_swevent_read,
+ .unthrottle = perf_swevent_unthrottle,
+};
+
+/*
+ * hrtimer based swevent callback
+ */
+
+static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
+{
+ enum hrtimer_restart ret = HRTIMER_RESTART;
+ struct perf_sample_data data;
+ struct pt_regs *regs;
+ struct perf_event *event;
+ u64 period;
+
+ event = container_of(hrtimer, struct perf_event, hw.hrtimer);
+ event->pmu->read(event);
+
+ data.addr = 0;
+ regs = get_irq_regs();
+ /*
+ * In case we exclude kernel IPs or are somehow not in interrupt
+ * context, provide the next best thing, the user IP.
+ */
+ if ((event->attr.exclude_kernel || !regs) &&
+ !event->attr.exclude_user)
+ regs = task_pt_regs(current);
+
+ if (regs) {
+ if (perf_event_overflow(event, 0, &data, regs))
+ ret = HRTIMER_NORESTART;
+ }
+
+ period = max_t(u64, 10000, event->hw.sample_period);
+ hrtimer_forward_now(hrtimer, ns_to_ktime(period));
+
+ return ret;
+}
+
+/*
+ * Software event: cpu wall time clock
+ */
+
+static void cpu_clock_perf_event_update(struct perf_event *event)
+{
+ int cpu = raw_smp_processor_id();
+ s64 prev;
+ u64 now;
+
+ now = cpu_clock(cpu);
+ prev = atomic64_read(&event->hw.prev_count);
+ atomic64_set(&event->hw.prev_count, now);
+ atomic64_add(now - prev, &event->count);
+}
+
+static int cpu_clock_perf_event_enable(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ int cpu = raw_smp_processor_id();
+
+ atomic64_set(&hwc->prev_count, cpu_clock(cpu));
+ hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ hwc->hrtimer.function = perf_swevent_hrtimer;
+ if (hwc->sample_period) {
+ u64 period = max_t(u64, 10000, hwc->sample_period);
+ __hrtimer_start_range_ns(&hwc->hrtimer,
+ ns_to_ktime(period), 0,
+ HRTIMER_MODE_REL, 0);
+ }
+
+ return 0;
+}
+
+static void cpu_clock_perf_event_disable(struct perf_event *event)
+{
+ if (event->hw.sample_period)
+ hrtimer_cancel(&event->hw.hrtimer);
+ cpu_clock_perf_event_update(event);
+}
+
+static void cpu_clock_perf_event_read(struct perf_event *event)
+{
+ cpu_clock_perf_event_update(event);
+}
+
+static const struct pmu perf_ops_cpu_clock = {
+ .enable = cpu_clock_perf_event_enable,
+ .disable = cpu_clock_perf_event_disable,
+ .read = cpu_clock_perf_event_read,
+};
+
+/*
+ * Software event: task time clock
+ */
+
+static void task_clock_perf_event_update(struct perf_event *event, u64 now)
+{
+ u64 prev;
+ s64 delta;
+
+ prev = atomic64_xchg(&event->hw.prev_count, now);
+ delta = now - prev;
+ atomic64_add(delta, &event->count);
+}
+
+static int task_clock_perf_event_enable(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ u64 now;
+
+ now = event->ctx->time;
+
+ atomic64_set(&hwc->prev_count, now);
+ hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ hwc->hrtimer.function = perf_swevent_hrtimer;
+ if (hwc->sample_period) {
+ u64 period = max_t(u64, 10000, hwc->sample_period);
+ __hrtimer_start_range_ns(&hwc->hrtimer,
+ ns_to_ktime(period), 0,
+ HRTIMER_MODE_REL, 0);
+ }
+
+ return 0;
+}
+
+static void task_clock_perf_event_disable(struct perf_event *event)
+{
+ if (event->hw.sample_period)
+ hrtimer_cancel(&event->hw.hrtimer);
+ task_clock_perf_event_update(event, event->ctx->time);
+
+}
+
+static void task_clock_perf_event_read(struct perf_event *event)
+{
+ u64 time;
+
+ if (!in_nmi()) {
+ update_context_time(event->ctx);
+ time = event->ctx->time;
+ } else {
+ u64 now = perf_clock();
+ u64 delta = now - event->ctx->timestamp;
+ time = event->ctx->time + delta;
+ }
+
+ task_clock_perf_event_update(event, time);
+}
+
+static const struct pmu perf_ops_task_clock = {
+ .enable = task_clock_perf_event_enable,
+ .disable = task_clock_perf_event_disable,
+ .read = task_clock_perf_event_read,
+};
+
+#ifdef CONFIG_EVENT_PROFILE
+void perf_tp_event(int event_id, u64 addr, u64 count, void *record,
+ int entry_size)
+{
+ struct perf_raw_record raw = {
+ .size = entry_size,
+ .data = record,
+ };
+
+ struct perf_sample_data data = {
+ .addr = addr,
+ .raw = &raw,
+ };
+
+ struct pt_regs *regs = get_irq_regs();
+
+ if (!regs)
+ regs = task_pt_regs(current);
+
+ do_perf_sw_event(PERF_TYPE_TRACEPOINT, event_id, count, 1,
+ &data, regs);
+}
+EXPORT_SYMBOL_GPL(perf_tp_event);
+
+extern int ftrace_profile_enable(int);
+extern void ftrace_profile_disable(int);
+
+static void tp_perf_event_destroy(struct perf_event *event)
+{
+ ftrace_profile_disable(event->attr.config);
+}
+
+static const struct pmu *tp_perf_event_init(struct perf_event *event)
+{
+ /*
+ * Raw tracepoint data is a severe data leak, only allow root to
+ * have these.
+ */
+ if ((event->attr.sample_type & PERF_SAMPLE_RAW) &&
+ perf_paranoid_tracepoint_raw() &&
+ !capable(CAP_SYS_ADMIN))
+ return ERR_PTR(-EPERM);
+
+ if (ftrace_profile_enable(event->attr.config))
+ return NULL;
+
+ event->destroy = tp_perf_event_destroy;
+
+ return &perf_ops_generic;
+}
+#else
+static const struct pmu *tp_perf_event_init(struct perf_event *event)
+{
+ return NULL;
+}
+#endif
+
+atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX];
+
+static void sw_perf_event_destroy(struct perf_event *event)
+{
+ u64 event_id = event->attr.config;
+
+ WARN_ON(event->parent);
+
+ atomic_dec(&perf_swevent_enabled[event_id]);
+}
+
+static const struct pmu *sw_perf_event_init(struct perf_event *event)
+{
+ const struct pmu *pmu = NULL;
+ u64 event_id = event->attr.config;
+
+ /*
+ * Software events (currently) can't in general distinguish
+ * between user, kernel and hypervisor events.
+ * However, context switches and cpu migrations are considered
+ * to be kernel events, and page faults are never hypervisor
+ * events.
+ */
+ switch (event_id) {
+ case PERF_COUNT_SW_CPU_CLOCK:
+ pmu = &perf_ops_cpu_clock;
+
+ break;
+ case PERF_COUNT_SW_TASK_CLOCK:
+ /*
+ * If the user instantiates this as a per-cpu event,
+ * use the cpu_clock event instead.
+ */
+ if (event->ctx->task)
+ pmu = &perf_ops_task_clock;
+ else
+ pmu = &perf_ops_cpu_clock;
+
+ break;
+ case PERF_COUNT_SW_PAGE_FAULTS:
+ case PERF_COUNT_SW_PAGE_FAULTS_MIN:
+ case PERF_COUNT_SW_PAGE_FAULTS_MAJ:
+ case PERF_COUNT_SW_CONTEXT_SWITCHES:
+ case PERF_COUNT_SW_CPU_MIGRATIONS:
+ if (!event->parent) {
+ atomic_inc(&perf_swevent_enabled[event_id]);
+ event->destroy = sw_perf_event_destroy;
+ }
+ pmu = &perf_ops_generic;
+ break;
+ }
+
+ return pmu;
+}
+
+/*
+ * Allocate and initialize a event structure
+ */
+static struct perf_event *
+perf_event_alloc(struct perf_event_attr *attr,
+ int cpu,
+ struct perf_event_context *ctx,
+ struct perf_event *group_leader,
+ struct perf_event *parent_event,
+ gfp_t gfpflags)
+{
+ const struct pmu *pmu;
+ struct perf_event *event;
+ struct hw_perf_event *hwc;
+ long err;
+
+ event = kzalloc(sizeof(*event), gfpflags);
+ if (!event)
+ return ERR_PTR(-ENOMEM);
+
+ /*
+ * Single events are their own group leaders, with an
+ * empty sibling list:
+ */
+ if (!group_leader)
+ group_leader = event;
+
+ mutex_init(&event->child_mutex);
+ INIT_LIST_HEAD(&event->child_list);
+
+ INIT_LIST_HEAD(&event->group_entry);
+ INIT_LIST_HEAD(&event->event_entry);
+ INIT_LIST_HEAD(&event->sibling_list);
+ init_waitqueue_head(&event->waitq);
+
+ mutex_init(&event->mmap_mutex);
+
+ event->cpu = cpu;
+ event->attr = *attr;
+ event->group_leader = group_leader;
+ event->pmu = NULL;
+ event->ctx = ctx;
+ event->oncpu = -1;
+
+ event->parent = parent_event;
+
+ event->ns = get_pid_ns(current->nsproxy->pid_ns);
+ event->id = atomic64_inc_return(&perf_event_id);
+
+ event->state = PERF_EVENT_STATE_INACTIVE;
+
+ if (attr->disabled)
+ event->state = PERF_EVENT_STATE_OFF;
+
+ pmu = NULL;
+
+ hwc = &event->hw;
+ hwc->sample_period = attr->sample_period;
+ if (attr->freq && attr->sample_freq)
+ hwc->sample_period = 1;
+ hwc->last_period = hwc->sample_period;
+
+ atomic64_set(&hwc->period_left, hwc->sample_period);
+
+ /*
+ * we currently do not support PERF_FORMAT_GROUP on inherited events
+ */
+ if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP))
+ goto done;
+
+ switch (attr->type) {
+ case PERF_TYPE_RAW:
+ case PERF_TYPE_HARDWARE:
+ case PERF_TYPE_HW_CACHE:
+ pmu = hw_perf_event_init(event);
+ break;
+
+ case PERF_TYPE_SOFTWARE:
+ pmu = sw_perf_event_init(event);
+ break;
+
+ case PERF_TYPE_TRACEPOINT:
+ pmu = tp_perf_event_init(event);
+ break;
+
+ default:
+ break;
+ }
+done:
+ err = 0;
+ if (!pmu)
+ err = -EINVAL;
+ else if (IS_ERR(pmu))
+ err = PTR_ERR(pmu);
+
+ if (err) {
+ if (event->ns)
+ put_pid_ns(event->ns);
+ kfree(event);
+ return ERR_PTR(err);
+ }
+
+ event->pmu = pmu;
+
+ if (!event->parent) {
+ atomic_inc(&nr_events);
+ if (event->attr.mmap)
+ atomic_inc(&nr_mmap_events);
+ if (event->attr.comm)
+ atomic_inc(&nr_comm_events);
+ if (event->attr.task)
+ atomic_inc(&nr_task_events);
+ }
+
+ return event;
+}
+
+static int perf_copy_attr(struct perf_event_attr __user *uattr,
+ struct perf_event_attr *attr)
+{
+ u32 size;
+ int ret;
+
+ if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0))
+ return -EFAULT;
+
+ /*
+ * zero the full structure, so that a short copy will be nice.
+ */
+ memset(attr, 0, sizeof(*attr));
+
+ ret = get_user(size, &uattr->size);
+ if (ret)
+ return ret;
+
+ if (size > PAGE_SIZE) /* silly large */
+ goto err_size;
+
+ if (!size) /* abi compat */
+ size = PERF_ATTR_SIZE_VER0;
+
+ if (size < PERF_ATTR_SIZE_VER0)
+ goto err_size;
+
+ /*
+ * If we're handed a bigger struct than we know of,
+ * ensure all the unknown bits are 0 - i.e. new
+ * user-space does not rely on any kernel feature
+ * extensions we dont know about yet.
+ */
+ if (size > sizeof(*attr)) {
+ unsigned char __user *addr;
+ unsigned char __user *end;
+ unsigned char val;
+
+ addr = (void __user *)uattr + sizeof(*attr);
+ end = (void __user *)uattr + size;
+
+ for (; addr < end; addr++) {
+ ret = get_user(val, addr);
+ if (ret)
+ return ret;
+ if (val)
+ goto err_size;
+ }
+ size = sizeof(*attr);
+ }
+
+ ret = copy_from_user(attr, uattr, size);
+ if (ret)
+ return -EFAULT;
+
+ /*
+ * If the type exists, the corresponding creation will verify
+ * the attr->config.
+ */
+ if (attr->type >= PERF_TYPE_MAX)
+ return -EINVAL;
+
+ if (attr->__reserved_1 || attr->__reserved_2 || attr->__reserved_3)
+ return -EINVAL;
+
+ if (attr->sample_type & ~(PERF_SAMPLE_MAX-1))
+ return -EINVAL;
+
+ if (attr->read_format & ~(PERF_FORMAT_MAX-1))
+ return -EINVAL;
+
+out:
+ return ret;
+
+err_size:
+ put_user(sizeof(*attr), &uattr->size);
+ ret = -E2BIG;
+ goto out;
+}
+
+int perf_event_set_output(struct perf_event *event, int output_fd)
+{
+ struct perf_event *output_event = NULL;
+ struct file *output_file = NULL;
+ struct perf_event *old_output;
+ int fput_needed = 0;
+ int ret = -EINVAL;
+
+ if (!output_fd)
+ goto set;
+
+ output_file = fget_light(output_fd, &fput_needed);
+ if (!output_file)
+ return -EBADF;
+
+ if (output_file->f_op != &perf_fops)
+ goto out;
+
+ output_event = output_file->private_data;
+
+ /* Don't chain output fds */
+ if (output_event->output)
+ goto out;
+
+ /* Don't set an output fd when we already have an output channel */
+ if (event->data)
+ goto out;
+
+ atomic_long_inc(&output_file->f_count);
+
+set:
+ mutex_lock(&event->mmap_mutex);
+ old_output = event->output;
+ rcu_assign_pointer(event->output, output_event);
+ mutex_unlock(&event->mmap_mutex);
+
+ if (old_output) {
+ /*
+ * we need to make sure no existing perf_output_*()
+ * is still referencing this event.
+ */
+ synchronize_rcu();
+ fput(old_output->filp);
+ }
+
+ ret = 0;
+out:
+ fput_light(output_file, fput_needed);
+ return ret;
+}
+
+/**
+ * sys_perf_event_open - open a performance event, associate it to a task/cpu
+ *
+ * @attr_uptr: event_id type attributes for monitoring/sampling
+ * @pid: target pid
+ * @cpu: target cpu
+ * @group_fd: group leader event fd
+ */
+SYSCALL_DEFINE5(perf_event_open,
+ struct perf_event_attr __user *, attr_uptr,
+ pid_t, pid, int, cpu, int, group_fd, unsigned long, flags)
+{
+ struct perf_event *event, *group_leader;
+ struct perf_event_attr attr;
+ struct perf_event_context *ctx;
+ struct file *event_file = NULL;
+ struct file *group_file = NULL;
+ int fput_needed = 0;
+ int fput_needed2 = 0;
+ int err;
+
+ /* for future expandability... */
+ if (flags & ~(PERF_FLAG_FD_NO_GROUP | PERF_FLAG_FD_OUTPUT))
+ return -EINVAL;
+
+ err = perf_copy_attr(attr_uptr, &attr);
+ if (err)
+ return err;
+
+ if (!attr.exclude_kernel) {
+ if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN))
+ return -EACCES;
+ }
+
+ if (attr.freq) {
+ if (attr.sample_freq > sysctl_perf_event_sample_rate)
+ return -EINVAL;
+ }
+
+ /*
+ * Get the target context (task or percpu):
+ */
+ ctx = find_get_context(pid, cpu);
+ if (IS_ERR(ctx))
+ return PTR_ERR(ctx);
+
+ /*
+ * Look up the group leader (we will attach this event to it):
+ */
+ group_leader = NULL;
+ if (group_fd != -1 && !(flags & PERF_FLAG_FD_NO_GROUP)) {
+ err = -EINVAL;
+ group_file = fget_light(group_fd, &fput_needed);
+ if (!group_file)
+ goto err_put_context;
+ if (group_file->f_op != &perf_fops)
+ goto err_put_context;
+
+ group_leader = group_file->private_data;
+ /*
+ * Do not allow a recursive hierarchy (this new sibling
+ * becoming part of another group-sibling):
+ */
+ if (group_leader->group_leader != group_leader)
+ goto err_put_context;
+ /*
+ * Do not allow to attach to a group in a different
+ * task or CPU context:
+ */
+ if (group_leader->ctx != ctx)
+ goto err_put_context;
+ /*
+ * Only a group leader can be exclusive or pinned
+ */
+ if (attr.exclusive || attr.pinned)
+ goto err_put_context;
+ }
+
+ event = perf_event_alloc(&attr, cpu, ctx, group_leader,
+ NULL, GFP_KERNEL);
+ err = PTR_ERR(event);
+ if (IS_ERR(event))
+ goto err_put_context;
+
+ err = anon_inode_getfd("[perf_event]", &perf_fops, event, 0);
+ if (err < 0)
+ goto err_free_put_context;
+
+ event_file = fget_light(err, &fput_needed2);
+ if (!event_file)
+ goto err_free_put_context;
+
+ if (flags & PERF_FLAG_FD_OUTPUT) {
+ err = perf_event_set_output(event, group_fd);
+ if (err)
+ goto err_fput_free_put_context;
+ }
+
+ event->filp = event_file;
+ WARN_ON_ONCE(ctx->parent_ctx);
+ mutex_lock(&ctx->mutex);
+ perf_install_in_context(ctx, event, cpu);
+ ++ctx->generation;
+ mutex_unlock(&ctx->mutex);
+
+ event->owner = current;
+ get_task_struct(current);
+ mutex_lock(&current->perf_event_mutex);
+ list_add_tail(&event->owner_entry, &current->perf_event_list);
+ mutex_unlock(&current->perf_event_mutex);
+
+err_fput_free_put_context:
+ fput_light(event_file, fput_needed2);
+
+err_free_put_context:
+ if (err < 0)
+ kfree(event);
+
+err_put_context:
+ if (err < 0)
+ put_ctx(ctx);
+
+ fput_light(group_file, fput_needed);
+
+ return err;
+}
+
+/*
+ * inherit a event from parent task to child task:
+ */
+static struct perf_event *
+inherit_event(struct perf_event *parent_event,
+ struct task_struct *parent,
+ struct perf_event_context *parent_ctx,
+ struct task_struct *child,
+ struct perf_event *group_leader,
+ struct perf_event_context *child_ctx)
+{
+ struct perf_event *child_event;
+
+ /*
+ * Instead of creating recursive hierarchies of events,
+ * we link inherited events back to the original parent,
+ * which has a filp for sure, which we use as the reference
+ * count:
+ */
+ if (parent_event->parent)
+ parent_event = parent_event->parent;
+
+ child_event = perf_event_alloc(&parent_event->attr,
+ parent_event->cpu, child_ctx,
+ group_leader, parent_event,
+ GFP_KERNEL);
+ if (IS_ERR(child_event))
+ return child_event;
+ get_ctx(child_ctx);
+
+ /*
+ * Make the child state follow the state of the parent event,
+ * not its attr.disabled bit. We hold the parent's mutex,
+ * so we won't race with perf_event_{en, dis}able_family.
+ */
+ if (parent_event->state >= PERF_EVENT_STATE_INACTIVE)
+ child_event->state = PERF_EVENT_STATE_INACTIVE;
+ else
+ child_event->state = PERF_EVENT_STATE_OFF;
+
+ if (parent_event->attr.freq)
+ child_event->hw.sample_period = parent_event->hw.sample_period;
+
+ /*
+ * Link it up in the child's context:
+ */
+ add_event_to_ctx(child_event, child_ctx);
+
+ /*
+ * Get a reference to the parent filp - we will fput it
+ * when the child event exits. This is safe to do because
+ * we are in the parent and we know that the filp still
+ * exists and has a nonzero count:
+ */
+ atomic_long_inc(&parent_event->filp->f_count);
+
+ /*
+ * Link this into the parent event's child list
+ */
+ WARN_ON_ONCE(parent_event->ctx->parent_ctx);
+ mutex_lock(&parent_event->child_mutex);
+ list_add_tail(&child_event->child_list, &parent_event->child_list);
+ mutex_unlock(&parent_event->child_mutex);
+
+ return child_event;
+}
+
+static int inherit_group(struct perf_event *parent_event,
+ struct task_struct *parent,
+ struct perf_event_context *parent_ctx,
+ struct task_struct *child,
+ struct perf_event_context *child_ctx)
+{
+ struct perf_event *leader;
+ struct perf_event *sub;
+ struct perf_event *child_ctr;
+
+ leader = inherit_event(parent_event, parent, parent_ctx,
+ child, NULL, child_ctx);
+ if (IS_ERR(leader))
+ return PTR_ERR(leader);
+ list_for_each_entry(sub, &parent_event->sibling_list, group_entry) {
+ child_ctr = inherit_event(sub, parent, parent_ctx,
+ child, leader, child_ctx);
+ if (IS_ERR(child_ctr))
+ return PTR_ERR(child_ctr);
+ }
+ return 0;
+}
+
+static void sync_child_event(struct perf_event *child_event,
+ struct task_struct *child)
+{
+ struct perf_event *parent_event = child_event->parent;
+ u64 child_val;
+
+ if (child_event->attr.inherit_stat)
+ perf_event_read_event(child_event, child);
+
+ child_val = atomic64_read(&child_event->count);
+
+ /*
+ * Add back the child's count to the parent's count:
+ */
+ atomic64_add(child_val, &parent_event->count);
+ atomic64_add(child_event->total_time_enabled,
+ &parent_event->child_total_time_enabled);
+ atomic64_add(child_event->total_time_running,
+ &parent_event->child_total_time_running);
+
+ /*
+ * Remove this event from the parent's list
+ */
+ WARN_ON_ONCE(parent_event->ctx->parent_ctx);
+ mutex_lock(&parent_event->child_mutex);
+ list_del_init(&child_event->child_list);
+ mutex_unlock(&parent_event->child_mutex);
+
+ /*
+ * Release the parent event, if this was the last
+ * reference to it.
+ */
+ fput(parent_event->filp);
+}
+
+static void
+__perf_event_exit_task(struct perf_event *child_event,
+ struct perf_event_context *child_ctx,
+ struct task_struct *child)
+{
+ struct perf_event *parent_event;
+
+ update_event_times(child_event);
+ perf_event_remove_from_context(child_event);
+
+ parent_event = child_event->parent;
+ /*
+ * It can happen that parent exits first, and has events
+ * that are still around due to the child reference. These
+ * events need to be zapped - but otherwise linger.
+ */
+ if (parent_event) {
+ sync_child_event(child_event, child);
+ free_event(child_event);
+ }
+}
+
+/*
+ * When a child task exits, feed back event values to parent events.
+ */
+void perf_event_exit_task(struct task_struct *child)
+{
+ struct perf_event *child_event, *tmp;
+ struct perf_event_context *child_ctx;
+ unsigned long flags;
+
+ if (likely(!child->perf_event_ctxp)) {
+ perf_event_task(child, NULL, 0);
+ return;
+ }
+
+ local_irq_save(flags);
+ /*
+ * We can't reschedule here because interrupts are disabled,
+ * and either child is current or it is a task that can't be
+ * scheduled, so we are now safe from rescheduling changing
+ * our context.
+ */
+ child_ctx = child->perf_event_ctxp;
+ __perf_event_task_sched_out(child_ctx);
+
+ /*
+ * Take the context lock here so that if find_get_context is
+ * reading child->perf_event_ctxp, we wait until it has
+ * incremented the context's refcount before we do put_ctx below.
+ */
+ spin_lock(&child_ctx->lock);
+ child->perf_event_ctxp = NULL;
+ /*
+ * If this context is a clone; unclone it so it can't get
+ * swapped to another process while we're removing all
+ * the events from it.
+ */
+ unclone_ctx(child_ctx);
+ spin_unlock_irqrestore(&child_ctx->lock, flags);
+
+ /*
+ * Report the task dead after unscheduling the events so that we
+ * won't get any samples after PERF_RECORD_EXIT. We can however still
+ * get a few PERF_RECORD_READ events.
+ */
+ perf_event_task(child, child_ctx, 0);
+
+ /*
+ * We can recurse on the same lock type through:
+ *
+ * __perf_event_exit_task()
+ * sync_child_event()
+ * fput(parent_event->filp)
+ * perf_release()
+ * mutex_lock(&ctx->mutex)
+ *
+ * But since its the parent context it won't be the same instance.
+ */
+ mutex_lock_nested(&child_ctx->mutex, SINGLE_DEPTH_NESTING);
+
+again:
+ list_for_each_entry_safe(child_event, tmp, &child_ctx->group_list,
+ group_entry)
+ __perf_event_exit_task(child_event, child_ctx, child);
+
+ /*
+ * If the last event was a group event, it will have appended all
+ * its siblings to the list, but we obtained 'tmp' before that which
+ * will still point to the list head terminating the iteration.
+ */
+ if (!list_empty(&child_ctx->group_list))
+ goto again;
+
+ mutex_unlock(&child_ctx->mutex);
+
+ put_ctx(child_ctx);
+}
+
+/*
+ * free an unexposed, unused context as created by inheritance by
+ * init_task below, used by fork() in case of fail.
+ */
+void perf_event_free_task(struct task_struct *task)
+{
+ struct perf_event_context *ctx = task->perf_event_ctxp;
+ struct perf_event *event, *tmp;
+
+ if (!ctx)
+ return;
+
+ mutex_lock(&ctx->mutex);
+again:
+ list_for_each_entry_safe(event, tmp, &ctx->group_list, group_entry) {
+ struct perf_event *parent = event->parent;
+
+ if (WARN_ON_ONCE(!parent))
+ continue;
+
+ mutex_lock(&parent->child_mutex);
+ list_del_init(&event->child_list);
+ mutex_unlock(&parent->child_mutex);
+
+ fput(parent->filp);
+
+ list_del_event(event, ctx);
+ free_event(event);
+ }
+
+ if (!list_empty(&ctx->group_list))
+ goto again;
+
+ mutex_unlock(&ctx->mutex);
+
+ put_ctx(ctx);
+}
+
+/*
+ * Initialize the perf_event context in task_struct
+ */
+int perf_event_init_task(struct task_struct *child)
+{
+ struct perf_event_context *child_ctx, *parent_ctx;
+ struct perf_event_context *cloned_ctx;
+ struct perf_event *event;
+ struct task_struct *parent = current;
+ int inherited_all = 1;
+ int ret = 0;
+
+ child->perf_event_ctxp = NULL;
+
+ mutex_init(&child->perf_event_mutex);
+ INIT_LIST_HEAD(&child->perf_event_list);
+
+ if (likely(!parent->perf_event_ctxp))
+ return 0;
+
+ /*
+ * This is executed from the parent task context, so inherit
+ * events that have been marked for cloning.
+ * First allocate and initialize a context for the child.
+ */
+
+ child_ctx = kmalloc(sizeof(struct perf_event_context), GFP_KERNEL);
+ if (!child_ctx)
+ return -ENOMEM;
+
+ __perf_event_init_context(child_ctx, child);
+ child->perf_event_ctxp = child_ctx;
+ get_task_struct(child);
+
+ /*
+ * If the parent's context is a clone, pin it so it won't get
+ * swapped under us.
+ */
+ parent_ctx = perf_pin_task_context(parent);
+
+ /*
+ * No need to check if parent_ctx != NULL here; since we saw
+ * it non-NULL earlier, the only reason for it to become NULL
+ * is if we exit, and since we're currently in the middle of
+ * a fork we can't be exiting at the same time.
+ */
+
+ /*
+ * Lock the parent list. No need to lock the child - not PID
+ * hashed yet and not running, so nobody can access it.
+ */
+ mutex_lock(&parent_ctx->mutex);
+
+ /*
+ * We dont have to disable NMIs - we are only looking at
+ * the list, not manipulating it:
+ */
+ list_for_each_entry_rcu(event, &parent_ctx->event_list, event_entry) {
+ if (event != event->group_leader)
+ continue;
+
+ if (!event->attr.inherit) {
+ inherited_all = 0;
+ continue;
+ }
+
+ ret = inherit_group(event, parent, parent_ctx,
+ child, child_ctx);
+ if (ret) {
+ inherited_all = 0;
+ break;
+ }
+ }
+
+ if (inherited_all) {
+ /*
+ * Mark the child context as a clone of the parent
+ * context, or of whatever the parent is a clone of.
+ * Note that if the parent is a clone, it could get
+ * uncloned at any point, but that doesn't matter
+ * because the list of events and the generation
+ * count can't have changed since we took the mutex.
+ */
+ cloned_ctx = rcu_dereference(parent_ctx->parent_ctx);
+ if (cloned_ctx) {
+ child_ctx->parent_ctx = cloned_ctx;
+ child_ctx->parent_gen = parent_ctx->parent_gen;
+ } else {
+ child_ctx->parent_ctx = parent_ctx;
+ child_ctx->parent_gen = parent_ctx->generation;
+ }
+ get_ctx(child_ctx->parent_ctx);
+ }
+
+ mutex_unlock(&parent_ctx->mutex);
+
+ perf_unpin_context(parent_ctx);
+
+ return ret;
+}
+
+static void __cpuinit perf_event_init_cpu(int cpu)
+{
+ struct perf_cpu_context *cpuctx;
+
+ cpuctx = &per_cpu(perf_cpu_context, cpu);
+ __perf_event_init_context(&cpuctx->ctx, NULL);
+
+ spin_lock(&perf_resource_lock);
+ cpuctx->max_pertask = perf_max_events - perf_reserved_percpu;
+ spin_unlock(&perf_resource_lock);
+
+ hw_perf_event_setup(cpu);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static void __perf_event_exit_cpu(void *info)
+{
+ struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+ struct perf_event_context *ctx = &cpuctx->ctx;
+ struct perf_event *event, *tmp;
+
+ list_for_each_entry_safe(event, tmp, &ctx->group_list, group_entry)
+ __perf_event_remove_from_context(event);
+}
+static void perf_event_exit_cpu(int cpu)
+{
+ struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
+ struct perf_event_context *ctx = &cpuctx->ctx;
+
+ mutex_lock(&ctx->mutex);
+ smp_call_function_single(cpu, __perf_event_exit_cpu, NULL, 1);
+ mutex_unlock(&ctx->mutex);
+}
+#else
+static inline void perf_event_exit_cpu(int cpu) { }
+#endif
+
+static int __cpuinit
+perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (long)hcpu;
+
+ switch (action) {
+
+ case CPU_UP_PREPARE:
+ case CPU_UP_PREPARE_FROZEN:
+ perf_event_init_cpu(cpu);
+ break;
+
+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
+ hw_perf_event_setup_online(cpu);
+ break;
+
+ case CPU_DOWN_PREPARE:
+ case CPU_DOWN_PREPARE_FROZEN:
+ perf_event_exit_cpu(cpu);
+ break;
+
+ default:
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+/*
+ * This has to have a higher priority than migration_notifier in sched.c.
+ */
+static struct notifier_block __cpuinitdata perf_cpu_nb = {
+ .notifier_call = perf_cpu_notify,
+ .priority = 20,
+};
+
+void __init perf_event_init(void)
+{
+ perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_UP_PREPARE,
+ (void *)(long)smp_processor_id());
+ perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_ONLINE,
+ (void *)(long)smp_processor_id());
+ register_cpu_notifier(&perf_cpu_nb);
+}
+
+static ssize_t perf_show_reserve_percpu(struct sysdev_class *class, char *buf)
+{
+ return sprintf(buf, "%d\n", perf_reserved_percpu);
+}
+
+static ssize_t
+perf_set_reserve_percpu(struct sysdev_class *class,
+ const char *buf,
+ size_t count)
+{
+ struct perf_cpu_context *cpuctx;
+ unsigned long val;
+ int err, cpu, mpt;
+
+ err = strict_strtoul(buf, 10, &val);
+ if (err)
+ return err;
+ if (val > perf_max_events)
+ return -EINVAL;
+
+ spin_lock(&perf_resource_lock);
+ perf_reserved_percpu = val;
+ for_each_online_cpu(cpu) {
+ cpuctx = &per_cpu(perf_cpu_context, cpu);
+ spin_lock_irq(&cpuctx->ctx.lock);
+ mpt = min(perf_max_events - cpuctx->ctx.nr_events,
+ perf_max_events - perf_reserved_percpu);
+ cpuctx->max_pertask = mpt;
+ spin_unlock_irq(&cpuctx->ctx.lock);
+ }
+ spin_unlock(&perf_resource_lock);
+
+ return count;
+}
+
+static ssize_t perf_show_overcommit(struct sysdev_class *class, char *buf)
+{
+ return sprintf(buf, "%d\n", perf_overcommit);
+}
+
+static ssize_t
+perf_set_overcommit(struct sysdev_class *class, const char *buf, size_t count)
+{
+ unsigned long val;
+ int err;
+
+ err = strict_strtoul(buf, 10, &val);
+ if (err)
+ return err;
+ if (val > 1)
+ return -EINVAL;
+
+ spin_lock(&perf_resource_lock);
+ perf_overcommit = val;
+ spin_unlock(&perf_resource_lock);
+
+ return count;
+}
+
+static SYSDEV_CLASS_ATTR(
+ reserve_percpu,
+ 0644,
+ perf_show_reserve_percpu,
+ perf_set_reserve_percpu
+ );
+
+static SYSDEV_CLASS_ATTR(
+ overcommit,
+ 0644,
+ perf_show_overcommit,
+ perf_set_overcommit
+ );
+
+static struct attribute *perfclass_attrs[] = {
+ &attr_reserve_percpu.attr,
+ &attr_overcommit.attr,
+ NULL
+};
+
+static struct attribute_group perfclass_attr_group = {
+ .attrs = perfclass_attrs,
+ .name = "perf_events",
+};
+
+static int __init perf_event_sysfs_init(void)
+{
+ return sysfs_create_group(&cpu_sysdev_class.kset.kobj,
+ &perfclass_attr_group);
+}
+device_initcall(perf_event_sysfs_init);
diff --git a/kernel/pid.c b/kernel/pid.c
index 31310b5d3f5..d3f722d20f9 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -40,7 +40,7 @@
#define pid_hashfn(nr, ns) \
hash_long((unsigned long)nr + (unsigned long)ns, pidhash_shift)
static struct hlist_head *pid_hash;
-static int pidhash_shift;
+static unsigned int pidhash_shift = 4;
struct pid init_struct_pid = INIT_STRUCT_PID;
int pid_max = PID_MAX_DEFAULT;
@@ -499,19 +499,12 @@ struct pid *find_ge_pid(int nr, struct pid_namespace *ns)
void __init pidhash_init(void)
{
int i, pidhash_size;
- unsigned long megabytes = nr_kernel_pages >> (20 - PAGE_SHIFT);
- pidhash_shift = max(4, fls(megabytes * 4));
- pidhash_shift = min(12, pidhash_shift);
+ pid_hash = alloc_large_system_hash("PID", sizeof(*pid_hash), 0, 18,
+ HASH_EARLY | HASH_SMALL,
+ &pidhash_shift, NULL, 4096);
pidhash_size = 1 << pidhash_shift;
- printk("PID hash table entries: %d (order: %d, %Zd bytes)\n",
- pidhash_size, pidhash_shift,
- pidhash_size * sizeof(struct hlist_head));
-
- pid_hash = alloc_bootmem(pidhash_size * sizeof(*(pid_hash)));
- if (!pid_hash)
- panic("Could not alloc pidhash!\n");
for (i = 0; i < pidhash_size; i++)
INIT_HLIST_HEAD(&pid_hash[i]);
}
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index 821722ae58a..86b3796b043 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -118,7 +118,7 @@ struct pid_namespace *copy_pid_ns(unsigned long flags, struct pid_namespace *old
{
if (!(flags & CLONE_NEWPID))
return get_pid_ns(old_ns);
- if (flags & CLONE_THREAD)
+ if (flags & (CLONE_THREAD|CLONE_PARENT))
return ERR_PTR(-EINVAL);
return create_pid_namespace(old_ns);
}
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index e33a21cb940..5c9dc228747 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -8,17 +8,18 @@
#include <linux/math64.h>
#include <asm/uaccess.h>
#include <linux/kernel_stat.h>
+#include <trace/events/timer.h>
/*
* Called after updating RLIMIT_CPU to set timer expiration if necessary.
*/
void update_rlimit_cpu(unsigned long rlim_new)
{
- cputime_t cputime;
+ cputime_t cputime = secs_to_cputime(rlim_new);
+ struct signal_struct *const sig = current->signal;
- cputime = secs_to_cputime(rlim_new);
- if (cputime_eq(current->signal->it_prof_expires, cputime_zero) ||
- cputime_gt(current->signal->it_prof_expires, cputime)) {
+ if (cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) ||
+ cputime_gt(sig->it[CPUCLOCK_PROF].expires, cputime)) {
spin_lock_irq(&current->sighand->siglock);
set_process_cpu_timer(current, CPUCLOCK_PROF, &cputime, NULL);
spin_unlock_irq(&current->sighand->siglock);
@@ -542,6 +543,17 @@ static void clear_dead_task(struct k_itimer *timer, union cpu_time_count now)
now);
}
+static inline int expires_gt(cputime_t expires, cputime_t new_exp)
+{
+ return cputime_eq(expires, cputime_zero) ||
+ cputime_gt(expires, new_exp);
+}
+
+static inline int expires_le(cputime_t expires, cputime_t new_exp)
+{
+ return !cputime_eq(expires, cputime_zero) &&
+ cputime_le(expires, new_exp);
+}
/*
* Insert the timer on the appropriate list before any timers that
* expire later. This must be called with the tasklist_lock held
@@ -586,34 +598,32 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now)
*/
if (CPUCLOCK_PERTHREAD(timer->it_clock)) {
+ union cpu_time_count *exp = &nt->expires;
+
switch (CPUCLOCK_WHICH(timer->it_clock)) {
default:
BUG();
case CPUCLOCK_PROF:
- if (cputime_eq(p->cputime_expires.prof_exp,
- cputime_zero) ||
- cputime_gt(p->cputime_expires.prof_exp,
- nt->expires.cpu))
- p->cputime_expires.prof_exp =
- nt->expires.cpu;
+ if (expires_gt(p->cputime_expires.prof_exp,
+ exp->cpu))
+ p->cputime_expires.prof_exp = exp->cpu;
break;
case CPUCLOCK_VIRT:
- if (cputime_eq(p->cputime_expires.virt_exp,
- cputime_zero) ||
- cputime_gt(p->cputime_expires.virt_exp,
- nt->expires.cpu))
- p->cputime_expires.virt_exp =
- nt->expires.cpu;
+ if (expires_gt(p->cputime_expires.virt_exp,
+ exp->cpu))
+ p->cputime_expires.virt_exp = exp->cpu;
break;
case CPUCLOCK_SCHED:
if (p->cputime_expires.sched_exp == 0 ||
- p->cputime_expires.sched_exp >
- nt->expires.sched)
+ p->cputime_expires.sched_exp > exp->sched)
p->cputime_expires.sched_exp =
- nt->expires.sched;
+ exp->sched;
break;
}
} else {
+ struct signal_struct *const sig = p->signal;
+ union cpu_time_count *exp = &timer->it.cpu.expires;
+
/*
* For a process timer, set the cached expiration time.
*/
@@ -621,30 +631,23 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now)
default:
BUG();
case CPUCLOCK_VIRT:
- if (!cputime_eq(p->signal->it_virt_expires,
- cputime_zero) &&
- cputime_lt(p->signal->it_virt_expires,
- timer->it.cpu.expires.cpu))
+ if (expires_le(sig->it[CPUCLOCK_VIRT].expires,
+ exp->cpu))
break;
- p->signal->cputime_expires.virt_exp =
- timer->it.cpu.expires.cpu;
+ sig->cputime_expires.virt_exp = exp->cpu;
break;
case CPUCLOCK_PROF:
- if (!cputime_eq(p->signal->it_prof_expires,
- cputime_zero) &&
- cputime_lt(p->signal->it_prof_expires,
- timer->it.cpu.expires.cpu))
+ if (expires_le(sig->it[CPUCLOCK_PROF].expires,
+ exp->cpu))
break;
- i = p->signal->rlim[RLIMIT_CPU].rlim_cur;
+ i = sig->rlim[RLIMIT_CPU].rlim_cur;
if (i != RLIM_INFINITY &&
- i <= cputime_to_secs(timer->it.cpu.expires.cpu))
+ i <= cputime_to_secs(exp->cpu))
break;
- p->signal->cputime_expires.prof_exp =
- timer->it.cpu.expires.cpu;
+ sig->cputime_expires.prof_exp = exp->cpu;
break;
case CPUCLOCK_SCHED:
- p->signal->cputime_expires.sched_exp =
- timer->it.cpu.expires.sched;
+ sig->cputime_expires.sched_exp = exp->sched;
break;
}
}
@@ -1071,6 +1074,40 @@ static void stop_process_timers(struct task_struct *tsk)
spin_unlock_irqrestore(&cputimer->lock, flags);
}
+static u32 onecputick;
+
+static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it,
+ cputime_t *expires, cputime_t cur_time, int signo)
+{
+ if (cputime_eq(it->expires, cputime_zero))
+ return;
+
+ if (cputime_ge(cur_time, it->expires)) {
+ if (!cputime_eq(it->incr, cputime_zero)) {
+ it->expires = cputime_add(it->expires, it->incr);
+ it->error += it->incr_error;
+ if (it->error >= onecputick) {
+ it->expires = cputime_sub(it->expires,
+ cputime_one_jiffy);
+ it->error -= onecputick;
+ }
+ } else {
+ it->expires = cputime_zero;
+ }
+
+ trace_itimer_expire(signo == SIGPROF ?
+ ITIMER_PROF : ITIMER_VIRTUAL,
+ tsk->signal->leader_pid, cur_time);
+ __group_send_sig_info(signo, SEND_SIG_PRIV, tsk);
+ }
+
+ if (!cputime_eq(it->expires, cputime_zero) &&
+ (cputime_eq(*expires, cputime_zero) ||
+ cputime_lt(it->expires, *expires))) {
+ *expires = it->expires;
+ }
+}
+
/*
* Check for any per-thread CPU timers that have fired and move them
* off the tsk->*_timers list onto the firing list. Per-thread timers
@@ -1090,10 +1127,10 @@ static void check_process_timers(struct task_struct *tsk,
* Don't sample the current process CPU clocks if there are no timers.
*/
if (list_empty(&timers[CPUCLOCK_PROF]) &&
- cputime_eq(sig->it_prof_expires, cputime_zero) &&
+ cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) &&
sig->rlim[RLIMIT_CPU].rlim_cur == RLIM_INFINITY &&
list_empty(&timers[CPUCLOCK_VIRT]) &&
- cputime_eq(sig->it_virt_expires, cputime_zero) &&
+ cputime_eq(sig->it[CPUCLOCK_VIRT].expires, cputime_zero) &&
list_empty(&timers[CPUCLOCK_SCHED])) {
stop_process_timers(tsk);
return;
@@ -1153,38 +1190,11 @@ static void check_process_timers(struct task_struct *tsk,
/*
* Check for the special case process timers.
*/
- if (!cputime_eq(sig->it_prof_expires, cputime_zero)) {
- if (cputime_ge(ptime, sig->it_prof_expires)) {
- /* ITIMER_PROF fires and reloads. */
- sig->it_prof_expires = sig->it_prof_incr;
- if (!cputime_eq(sig->it_prof_expires, cputime_zero)) {
- sig->it_prof_expires = cputime_add(
- sig->it_prof_expires, ptime);
- }
- __group_send_sig_info(SIGPROF, SEND_SIG_PRIV, tsk);
- }
- if (!cputime_eq(sig->it_prof_expires, cputime_zero) &&
- (cputime_eq(prof_expires, cputime_zero) ||
- cputime_lt(sig->it_prof_expires, prof_expires))) {
- prof_expires = sig->it_prof_expires;
- }
- }
- if (!cputime_eq(sig->it_virt_expires, cputime_zero)) {
- if (cputime_ge(utime, sig->it_virt_expires)) {
- /* ITIMER_VIRTUAL fires and reloads. */
- sig->it_virt_expires = sig->it_virt_incr;
- if (!cputime_eq(sig->it_virt_expires, cputime_zero)) {
- sig->it_virt_expires = cputime_add(
- sig->it_virt_expires, utime);
- }
- __group_send_sig_info(SIGVTALRM, SEND_SIG_PRIV, tsk);
- }
- if (!cputime_eq(sig->it_virt_expires, cputime_zero) &&
- (cputime_eq(virt_expires, cputime_zero) ||
- cputime_lt(sig->it_virt_expires, virt_expires))) {
- virt_expires = sig->it_virt_expires;
- }
- }
+ check_cpu_itimer(tsk, &sig->it[CPUCLOCK_PROF], &prof_expires, ptime,
+ SIGPROF);
+ check_cpu_itimer(tsk, &sig->it[CPUCLOCK_VIRT], &virt_expires, utime,
+ SIGVTALRM);
+
if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
unsigned long psecs = cputime_to_secs(ptime);
cputime_t x;
@@ -1457,7 +1467,7 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx,
if (!cputime_eq(*oldval, cputime_zero)) {
if (cputime_le(*oldval, now.cpu)) {
/* Just about to fire. */
- *oldval = jiffies_to_cputime(1);
+ *oldval = cputime_one_jiffy;
} else {
*oldval = cputime_sub(*oldval, now.cpu);
}
@@ -1703,10 +1713,15 @@ static __init int init_posix_cpu_timers(void)
.nsleep = thread_cpu_nsleep,
.nsleep_restart = thread_cpu_nsleep_restart,
};
+ struct timespec ts;
register_posix_clock(CLOCK_PROCESS_CPUTIME_ID, &process);
register_posix_clock(CLOCK_THREAD_CPUTIME_ID, &thread);
+ cputime_to_timespec(cputime_one_jiffy, &ts);
+ onecputick = ts.tv_nsec;
+ WARN_ON(ts.tv_sec != 0);
+
return 0;
}
__initcall(init_posix_cpu_timers);
diff --git a/kernel/power/console.c b/kernel/power/console.c
index a3961b205de..5187136fe1d 100644
--- a/kernel/power/console.c
+++ b/kernel/power/console.c
@@ -14,56 +14,13 @@
#define SUSPEND_CONSOLE (MAX_NR_CONSOLES-1)
static int orig_fgconsole, orig_kmsg;
-static int disable_vt_switch;
-
-/*
- * Normally during a suspend, we allocate a new console and switch to it.
- * When we resume, we switch back to the original console. This switch
- * can be slow, so on systems where the framebuffer can handle restoration
- * of video registers anyways, there's little point in doing the console
- * switch. This function allows you to disable it by passing it '0'.
- */
-void pm_set_vt_switch(int do_switch)
-{
- acquire_console_sem();
- disable_vt_switch = !do_switch;
- release_console_sem();
-}
-EXPORT_SYMBOL(pm_set_vt_switch);
int pm_prepare_console(void)
{
- acquire_console_sem();
-
- if (disable_vt_switch) {
- release_console_sem();
- return 0;
- }
-
- orig_fgconsole = fg_console;
-
- if (vc_allocate(SUSPEND_CONSOLE)) {
- /* we can't have a free VC for now. Too bad,
- * we don't want to mess the screen for now. */
- release_console_sem();
+ orig_fgconsole = vt_move_to_console(SUSPEND_CONSOLE, 1);
+ if (orig_fgconsole < 0)
return 1;
- }
- if (set_console(SUSPEND_CONSOLE)) {
- /*
- * We're unable to switch to the SUSPEND_CONSOLE.
- * Let the calling function know so it can decide
- * what to do.
- */
- release_console_sem();
- return 1;
- }
- release_console_sem();
-
- if (vt_waitactive(SUSPEND_CONSOLE)) {
- pr_debug("Suspend: Can't switch VCs.");
- return 1;
- }
orig_kmsg = kmsg_redirect;
kmsg_redirect = SUSPEND_CONSOLE;
return 0;
@@ -71,19 +28,9 @@ int pm_prepare_console(void)
void pm_restore_console(void)
{
- acquire_console_sem();
- if (disable_vt_switch) {
- release_console_sem();
- return;
- }
- set_console(orig_fgconsole);
- release_console_sem();
-
- if (vt_waitactive(orig_fgconsole)) {
- pr_debug("Resume: Can't switch VCs.");
- return;
+ if (orig_fgconsole >= 0) {
+ vt_move_to_console(orig_fgconsole, 0);
+ kmsg_redirect = orig_kmsg;
}
-
- kmsg_redirect = orig_kmsg;
}
#endif
diff --git a/kernel/power/process.c b/kernel/power/process.c
index da2072d7381..cc2e55373b6 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -9,6 +9,7 @@
#undef DEBUG
#include <linux/interrupt.h>
+#include <linux/oom.h>
#include <linux/suspend.h>
#include <linux/module.h>
#include <linux/syscalls.h>
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 97955b0e44f..36cb168e433 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -619,7 +619,7 @@ __register_nosave_region(unsigned long start_pfn, unsigned long end_pfn,
BUG_ON(!region);
} else
/* This allocation cannot fail */
- region = alloc_bootmem_low(sizeof(struct nosave_region));
+ region = alloc_bootmem(sizeof(struct nosave_region));
region->start_pfn = start_pfn;
region->end_pfn = end_pfn;
list_add_tail(&region->list, &nosave_regions);
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 8ba052c86d4..b101cdc4df3 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -13,7 +13,6 @@
#include <linux/module.h>
#include <linux/file.h>
-#include <linux/utsname.h>
#include <linux/delay.h>
#include <linux/bitops.h>
#include <linux/genhd.h>
diff --git a/kernel/printk.c b/kernel/printk.c
index 602033acd6c..f38b07f78a4 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -206,12 +206,11 @@ __setup("log_buf_len=", log_buf_len_setup);
#ifdef CONFIG_BOOT_PRINTK_DELAY
static unsigned int boot_delay; /* msecs delay after each printk during bootup */
-static unsigned long long printk_delay_msec; /* per msec, based on boot_delay */
+static unsigned long long loops_per_msec; /* based on boot_delay */
static int __init boot_delay_setup(char *str)
{
unsigned long lpj;
- unsigned long long loops_per_msec;
lpj = preset_lpj ? preset_lpj : 1000000; /* some guess */
loops_per_msec = (unsigned long long)lpj / 1000 * HZ;
@@ -220,10 +219,9 @@ static int __init boot_delay_setup(char *str)
if (boot_delay > 10 * 1000)
boot_delay = 0;
- printk_delay_msec = loops_per_msec;
- printk(KERN_DEBUG "boot_delay: %u, preset_lpj: %ld, lpj: %lu, "
- "HZ: %d, printk_delay_msec: %llu\n",
- boot_delay, preset_lpj, lpj, HZ, printk_delay_msec);
+ pr_debug("boot_delay: %u, preset_lpj: %ld, lpj: %lu, "
+ "HZ: %d, loops_per_msec: %llu\n",
+ boot_delay, preset_lpj, lpj, HZ, loops_per_msec);
return 1;
}
__setup("boot_delay=", boot_delay_setup);
@@ -236,7 +234,7 @@ static void boot_delay_msec(void)
if (boot_delay == 0 || system_state != SYSTEM_BOOTING)
return;
- k = (unsigned long long)printk_delay_msec * boot_delay;
+ k = (unsigned long long)loops_per_msec * boot_delay;
timeout = jiffies + msecs_to_jiffies(boot_delay);
while (k) {
@@ -655,6 +653,20 @@ static int recursion_bug;
static int new_text_line = 1;
static char printk_buf[1024];
+int printk_delay_msec __read_mostly;
+
+static inline void printk_delay(void)
+{
+ if (unlikely(printk_delay_msec)) {
+ int m = printk_delay_msec;
+
+ while (m--) {
+ mdelay(1);
+ touch_nmi_watchdog();
+ }
+ }
+}
+
asmlinkage int vprintk(const char *fmt, va_list args)
{
int printed_len = 0;
@@ -664,6 +676,7 @@ asmlinkage int vprintk(const char *fmt, va_list args)
char *p;
boot_delay_msec();
+ printk_delay();
preempt_disable();
/* This stops the holder of console_sem just where we want him */
diff --git a/kernel/profile.c b/kernel/profile.c
index 419250ebec4..a55d3a367ae 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -442,48 +442,51 @@ void profile_tick(int type)
#ifdef CONFIG_PROC_FS
#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
#include <asm/uaccess.h>
-static int prof_cpu_mask_read_proc(char *page, char **start, off_t off,
- int count, int *eof, void *data)
+static int prof_cpu_mask_proc_show(struct seq_file *m, void *v)
{
- int len = cpumask_scnprintf(page, count, data);
- if (count - len < 2)
- return -EINVAL;
- len += sprintf(page + len, "\n");
- return len;
+ seq_cpumask(m, prof_cpu_mask);
+ seq_putc(m, '\n');
+ return 0;
}
-static int prof_cpu_mask_write_proc(struct file *file,
- const char __user *buffer, unsigned long count, void *data)
+static int prof_cpu_mask_proc_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, prof_cpu_mask_proc_show, NULL);
+}
+
+static ssize_t prof_cpu_mask_proc_write(struct file *file,
+ const char __user *buffer, size_t count, loff_t *pos)
{
- struct cpumask *mask = data;
- unsigned long full_count = count, err;
cpumask_var_t new_value;
+ int err;
if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
return -ENOMEM;
err = cpumask_parse_user(buffer, count, new_value);
if (!err) {
- cpumask_copy(mask, new_value);
- err = full_count;
+ cpumask_copy(prof_cpu_mask, new_value);
+ err = count;
}
free_cpumask_var(new_value);
return err;
}
+static const struct file_operations prof_cpu_mask_proc_fops = {
+ .open = prof_cpu_mask_proc_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+ .write = prof_cpu_mask_proc_write,
+};
+
void create_prof_cpu_mask(struct proc_dir_entry *root_irq_dir)
{
- struct proc_dir_entry *entry;
-
/* create /proc/irq/prof_cpu_mask */
- entry = create_proc_entry("prof_cpu_mask", 0600, root_irq_dir);
- if (!entry)
- return;
- entry->data = prof_cpu_mask;
- entry->read_proc = prof_cpu_mask_read_proc;
- entry->write_proc = prof_cpu_mask_write_proc;
+ proc_create("prof_cpu_mask", 0600, root_irq_dir, &prof_cpu_mask_proc_fops);
}
/*
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 307c285af59..23bd09cd042 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -266,9 +266,10 @@ static int ignoring_children(struct sighand_struct *sigh)
* or self-reaping. Do notification now if it would have happened earlier.
* If it should reap itself, return true.
*
- * If it's our own child, there is no notification to do.
- * But if our normal children self-reap, then this child
- * was prevented by ptrace and we must reap it now.
+ * If it's our own child, there is no notification to do. But if our normal
+ * children self-reap, then this child was prevented by ptrace and we must
+ * reap it now, in that case we must also wake up sub-threads sleeping in
+ * do_wait().
*/
static bool __ptrace_detach(struct task_struct *tracer, struct task_struct *p)
{
@@ -278,8 +279,10 @@ static bool __ptrace_detach(struct task_struct *tracer, struct task_struct *p)
if (!task_detached(p) && thread_group_empty(p)) {
if (!same_thread_group(p->real_parent, tracer))
do_notify_parent(p, p->exit_signal);
- else if (ignoring_children(tracer->sighand))
+ else if (ignoring_children(tracer->sighand)) {
+ __wake_up_parent(p, tracer);
p->exit_signal = -1;
+ }
}
if (task_detached(p)) {
/* Mark it as in the process of being reaped. */
diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c
index bd5d5c8e514..37ac4548308 100644
--- a/kernel/rcupdate.c
+++ b/kernel/rcupdate.c
@@ -19,7 +19,7 @@
*
* Authors: Dipankar Sarma <dipankar@in.ibm.com>
* Manfred Spraul <manfred@colorfullife.com>
- *
+ *
* Based on the original work by Paul McKenney <paulmck@us.ibm.com>
* and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen.
* Papers:
@@ -27,7 +27,7 @@
* http://lse.sourceforge.net/locking/rclock_OLS.2001.05.01c.sc.pdf (OLS2001)
*
* For detailed explanation of Read-Copy Update mechanism see -
- * http://lse.sourceforge.net/locking/rcupdate.html
+ * http://lse.sourceforge.net/locking/rcupdate.html
*
*/
#include <linux/types.h>
@@ -74,6 +74,8 @@ void wakeme_after_rcu(struct rcu_head *head)
complete(&rcu->completion);
}
+#ifdef CONFIG_TREE_PREEMPT_RCU
+
/**
* synchronize_rcu - wait until a grace period has elapsed.
*
@@ -87,7 +89,7 @@ void synchronize_rcu(void)
{
struct rcu_synchronize rcu;
- if (rcu_blocking_is_gp())
+ if (!rcu_scheduler_active)
return;
init_completion(&rcu.completion);
@@ -98,6 +100,46 @@ void synchronize_rcu(void)
}
EXPORT_SYMBOL_GPL(synchronize_rcu);
+#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+
+/**
+ * synchronize_sched - wait until an rcu-sched grace period has elapsed.
+ *
+ * Control will return to the caller some time after a full rcu-sched
+ * grace period has elapsed, in other words after all currently executing
+ * rcu-sched read-side critical sections have completed. These read-side
+ * critical sections are delimited by rcu_read_lock_sched() and
+ * rcu_read_unlock_sched(), and may be nested. Note that preempt_disable(),
+ * local_irq_disable(), and so on may be used in place of
+ * rcu_read_lock_sched().
+ *
+ * This means that all preempt_disable code sequences, including NMI and
+ * hardware-interrupt handlers, in progress on entry will have completed
+ * before this primitive returns. However, this does not guarantee that
+ * softirq handlers will have completed, since in some kernels, these
+ * handlers can run in process context, and can block.
+ *
+ * This primitive provides the guarantees made by the (now removed)
+ * synchronize_kernel() API. In contrast, synchronize_rcu() only
+ * guarantees that rcu_read_lock() sections will have completed.
+ * In "classic RCU", these two guarantees happen to be one and
+ * the same, but can differ in realtime RCU implementations.
+ */
+void synchronize_sched(void)
+{
+ struct rcu_synchronize rcu;
+
+ if (rcu_blocking_is_gp())
+ return;
+
+ init_completion(&rcu.completion);
+ /* Will wake me after RCU finished. */
+ call_rcu_sched(&rcu.head, wakeme_after_rcu);
+ /* Wait for it. */
+ wait_for_completion(&rcu.completion);
+}
+EXPORT_SYMBOL_GPL(synchronize_sched);
+
/**
* synchronize_rcu_bh - wait until an rcu_bh grace period has elapsed.
*
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index b33db539a8a..233768f21f9 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -18,7 +18,7 @@
* Copyright (C) IBM Corporation, 2005, 2006
*
* Authors: Paul E. McKenney <paulmck@us.ibm.com>
- * Josh Triplett <josh@freedesktop.org>
+ * Josh Triplett <josh@freedesktop.org>
*
* See also: Documentation/RCU/torture.txt
*/
@@ -50,7 +50,7 @@
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and "
- "Josh Triplett <josh@freedesktop.org>");
+ "Josh Triplett <josh@freedesktop.org>");
static int nreaders = -1; /* # reader threads, defaults to 2*ncpus */
static int nfakewriters = 4; /* # fake writer threads */
@@ -110,8 +110,8 @@ struct rcu_torture {
};
static LIST_HEAD(rcu_torture_freelist);
-static struct rcu_torture *rcu_torture_current = NULL;
-static long rcu_torture_current_version = 0;
+static struct rcu_torture *rcu_torture_current;
+static long rcu_torture_current_version;
static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN];
static DEFINE_SPINLOCK(rcu_torture_lock);
static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) =
@@ -124,11 +124,11 @@ static atomic_t n_rcu_torture_alloc_fail;
static atomic_t n_rcu_torture_free;
static atomic_t n_rcu_torture_mberror;
static atomic_t n_rcu_torture_error;
-static long n_rcu_torture_timers = 0;
+static long n_rcu_torture_timers;
static struct list_head rcu_torture_removed;
static cpumask_var_t shuffle_tmp_mask;
-static int stutter_pause_test = 0;
+static int stutter_pause_test;
#if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE)
#define RCUTORTURE_RUNNABLE_INIT 1
@@ -267,7 +267,8 @@ struct rcu_torture_ops {
int irq_capable;
char *name;
};
-static struct rcu_torture_ops *cur_ops = NULL;
+
+static struct rcu_torture_ops *cur_ops;
/*
* Definitions for rcu torture testing.
@@ -281,14 +282,17 @@ static int rcu_torture_read_lock(void) __acquires(RCU)
static void rcu_read_delay(struct rcu_random_state *rrsp)
{
- long delay;
- const long longdelay = 200;
+ const unsigned long shortdelay_us = 200;
+ const unsigned long longdelay_ms = 50;
- /* We want there to be long-running readers, but not all the time. */
+ /* We want a short delay sometimes to make a reader delay the grace
+ * period, and we want a long delay occasionally to trigger
+ * force_quiescent_state. */
- delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay);
- if (!delay)
- udelay(longdelay);
+ if (!(rcu_random(rrsp) % (nrealreaders * 2000 * longdelay_ms)))
+ mdelay(longdelay_ms);
+ if (!(rcu_random(rrsp) % (nrealreaders * 2 * shortdelay_us)))
+ udelay(shortdelay_us);
}
static void rcu_torture_read_unlock(int idx) __releases(RCU)
@@ -339,8 +343,8 @@ static struct rcu_torture_ops rcu_ops = {
.sync = synchronize_rcu,
.cb_barrier = rcu_barrier,
.stats = NULL,
- .irq_capable = 1,
- .name = "rcu"
+ .irq_capable = 1,
+ .name = "rcu"
};
static void rcu_sync_torture_deferred_free(struct rcu_torture *p)
@@ -638,7 +642,8 @@ rcu_torture_writer(void *arg)
do {
schedule_timeout_uninterruptible(1);
- if ((rp = rcu_torture_alloc()) == NULL)
+ rp = rcu_torture_alloc();
+ if (rp == NULL)
continue;
rp->rtort_pipe_count = 0;
udelay(rcu_random(&rand) & 0x3ff);
@@ -1110,7 +1115,7 @@ rcu_torture_init(void)
printk(KERN_ALERT "rcutorture: invalid torture type: \"%s\"\n",
torture_type);
mutex_unlock(&fullstop_mutex);
- return (-EINVAL);
+ return -EINVAL;
}
if (cur_ops->init)
cur_ops->init(); /* no "goto unwind" prior to this point!!! */
@@ -1161,7 +1166,7 @@ rcu_torture_init(void)
goto unwind;
}
fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]),
- GFP_KERNEL);
+ GFP_KERNEL);
if (fakewriter_tasks == NULL) {
VERBOSE_PRINTK_ERRSTRING("out of memory");
firsterr = -ENOMEM;
@@ -1170,7 +1175,7 @@ rcu_torture_init(void)
for (i = 0; i < nfakewriters; i++) {
VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task");
fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL,
- "rcu_torture_fakewriter");
+ "rcu_torture_fakewriter");
if (IS_ERR(fakewriter_tasks[i])) {
firsterr = PTR_ERR(fakewriter_tasks[i]);
VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter");
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 6b11b07cfe7..52b06f6e158 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -25,7 +25,7 @@
* and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen.
*
* For detailed explanation of Read-Copy Update mechanism see -
- * Documentation/RCU
+ * Documentation/RCU
*/
#include <linux/types.h>
#include <linux/kernel.h>
@@ -107,27 +107,23 @@ static void __cpuinit rcu_init_percpu_data(int cpu, struct rcu_state *rsp,
*/
void rcu_sched_qs(int cpu)
{
- unsigned long flags;
struct rcu_data *rdp;
- local_irq_save(flags);
rdp = &per_cpu(rcu_sched_data, cpu);
- rdp->passed_quiesc = 1;
rdp->passed_quiesc_completed = rdp->completed;
- rcu_preempt_qs(cpu);
- local_irq_restore(flags);
+ barrier();
+ rdp->passed_quiesc = 1;
+ rcu_preempt_note_context_switch(cpu);
}
void rcu_bh_qs(int cpu)
{
- unsigned long flags;
struct rcu_data *rdp;
- local_irq_save(flags);
rdp = &per_cpu(rcu_bh_data, cpu);
- rdp->passed_quiesc = 1;
rdp->passed_quiesc_completed = rdp->completed;
- local_irq_restore(flags);
+ barrier();
+ rdp->passed_quiesc = 1;
}
#ifdef CONFIG_NO_HZ
@@ -605,8 +601,6 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
{
struct rcu_data *rdp = rsp->rda[smp_processor_id()];
struct rcu_node *rnp = rcu_get_root(rsp);
- struct rcu_node *rnp_cur;
- struct rcu_node *rnp_end;
if (!cpu_needs_another_gp(rsp, rdp)) {
spin_unlock_irqrestore(&rnp->lock, flags);
@@ -615,6 +609,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
/* Advance to a new grace period and initialize state. */
rsp->gpnum++;
+ WARN_ON_ONCE(rsp->signaled == RCU_GP_INIT);
rsp->signaled = RCU_GP_INIT; /* Hold off force_quiescent_state. */
rsp->jiffies_force_qs = jiffies + RCU_JIFFIES_TILL_FORCE_QS;
record_gp_stall_check_time(rsp);
@@ -631,7 +626,9 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
/* Special-case the common single-level case. */
if (NUM_RCU_NODES == 1) {
+ rcu_preempt_check_blocked_tasks(rnp);
rnp->qsmask = rnp->qsmaskinit;
+ rnp->gpnum = rsp->gpnum;
rsp->signaled = RCU_SIGNAL_INIT; /* force_quiescent_state OK. */
spin_unlock_irqrestore(&rnp->lock, flags);
return;
@@ -644,42 +641,28 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
spin_lock(&rsp->onofflock); /* irqs already disabled. */
/*
- * Set the quiescent-state-needed bits in all the non-leaf RCU
- * nodes for all currently online CPUs. This operation relies
- * on the layout of the hierarchy within the rsp->node[] array.
- * Note that other CPUs will access only the leaves of the
- * hierarchy, which still indicate that no grace period is in
- * progress. In addition, we have excluded CPU-hotplug operations.
- *
- * We therefore do not need to hold any locks. Any required
- * memory barriers will be supplied by the locks guarding the
- * leaf rcu_nodes in the hierarchy.
- */
-
- rnp_end = rsp->level[NUM_RCU_LVLS - 1];
- for (rnp_cur = &rsp->node[0]; rnp_cur < rnp_end; rnp_cur++)
- rnp_cur->qsmask = rnp_cur->qsmaskinit;
-
- /*
- * Now set up the leaf nodes. Here we must be careful. First,
- * we need to hold the lock in order to exclude other CPUs, which
- * might be contending for the leaf nodes' locks. Second, as
- * soon as we initialize a given leaf node, its CPUs might run
- * up the rest of the hierarchy. We must therefore acquire locks
- * for each node that we touch during this stage. (But we still
- * are excluding CPU-hotplug operations.)
+ * Set the quiescent-state-needed bits in all the rcu_node
+ * structures for all currently online CPUs in breadth-first
+ * order, starting from the root rcu_node structure. This
+ * operation relies on the layout of the hierarchy within the
+ * rsp->node[] array. Note that other CPUs will access only
+ * the leaves of the hierarchy, which still indicate that no
+ * grace period is in progress, at least until the corresponding
+ * leaf node has been initialized. In addition, we have excluded
+ * CPU-hotplug operations.
*
* Note that the grace period cannot complete until we finish
* the initialization process, as there will be at least one
* qsmask bit set in the root node until that time, namely the
- * one corresponding to this CPU.
+ * one corresponding to this CPU, due to the fact that we have
+ * irqs disabled.
*/
- rnp_end = &rsp->node[NUM_RCU_NODES];
- rnp_cur = rsp->level[NUM_RCU_LVLS - 1];
- for (; rnp_cur < rnp_end; rnp_cur++) {
- spin_lock(&rnp_cur->lock); /* irqs already disabled. */
- rnp_cur->qsmask = rnp_cur->qsmaskinit;
- spin_unlock(&rnp_cur->lock); /* irqs already disabled. */
+ for (rnp = &rsp->node[0]; rnp < &rsp->node[NUM_RCU_NODES]; rnp++) {
+ spin_lock(&rnp->lock); /* irqs already disabled. */
+ rcu_preempt_check_blocked_tasks(rnp);
+ rnp->qsmask = rnp->qsmaskinit;
+ rnp->gpnum = rsp->gpnum;
+ spin_unlock(&rnp->lock); /* irqs already disabled. */
}
rsp->signaled = RCU_SIGNAL_INIT; /* force_quiescent_state now OK. */
@@ -722,6 +705,7 @@ rcu_process_gp_end(struct rcu_state *rsp, struct rcu_data *rdp)
static void cpu_quiet_msk_finish(struct rcu_state *rsp, unsigned long flags)
__releases(rnp->lock)
{
+ WARN_ON_ONCE(rsp->completed == rsp->gpnum);
rsp->completed = rsp->gpnum;
rcu_process_gp_end(rsp, rsp->rda[smp_processor_id()]);
rcu_start_gp(rsp, flags); /* releases root node's rnp->lock. */
@@ -739,6 +723,8 @@ cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp, struct rcu_node *rnp,
unsigned long flags)
__releases(rnp->lock)
{
+ struct rcu_node *rnp_c;
+
/* Walk up the rcu_node hierarchy. */
for (;;) {
if (!(rnp->qsmask & mask)) {
@@ -762,8 +748,10 @@ cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp, struct rcu_node *rnp,
break;
}
spin_unlock_irqrestore(&rnp->lock, flags);
+ rnp_c = rnp;
rnp = rnp->parent;
spin_lock_irqsave(&rnp->lock, flags);
+ WARN_ON_ONCE(rnp_c->qsmask);
}
/*
@@ -776,10 +764,10 @@ cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp, struct rcu_node *rnp,
/*
* Record a quiescent state for the specified CPU, which must either be
- * the current CPU or an offline CPU. The lastcomp argument is used to
- * make sure we are still in the grace period of interest. We don't want
- * to end the current grace period based on quiescent states detected in
- * an earlier grace period!
+ * the current CPU. The lastcomp argument is used to make sure we are
+ * still in the grace period of interest. We don't want to end the current
+ * grace period based on quiescent states detected in an earlier grace
+ * period!
*/
static void
cpu_quiet(int cpu, struct rcu_state *rsp, struct rcu_data *rdp, long lastcomp)
@@ -814,7 +802,6 @@ cpu_quiet(int cpu, struct rcu_state *rsp, struct rcu_data *rdp, long lastcomp)
* This GP can't end until cpu checks in, so all of our
* callbacks can be processed during the next GP.
*/
- rdp = rsp->rda[smp_processor_id()];
rdp->nxttail[RCU_NEXT_READY_TAIL] = rdp->nxttail[RCU_NEXT_TAIL];
cpu_quiet_msk(mask, rsp, rnp, flags); /* releases rnp->lock */
@@ -872,7 +859,7 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
spin_lock_irqsave(&rsp->onofflock, flags);
/* Remove the outgoing CPU from the masks in the rcu_node hierarchy. */
- rnp = rdp->mynode;
+ rnp = rdp->mynode; /* this is the outgoing CPU's rnp. */
mask = rdp->grpmask; /* rnp->grplo is constant. */
do {
spin_lock(&rnp->lock); /* irqs already disabled. */
@@ -881,7 +868,7 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
spin_unlock(&rnp->lock); /* irqs remain disabled. */
break;
}
- rcu_preempt_offline_tasks(rsp, rnp);
+ rcu_preempt_offline_tasks(rsp, rnp, rdp);
mask = rnp->grpmask;
spin_unlock(&rnp->lock); /* irqs remain disabled. */
rnp = rnp->parent;
@@ -890,9 +877,6 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
spin_unlock(&rsp->onofflock); /* irqs remain disabled. */
- /* Being offline is a quiescent state, so go record it. */
- cpu_quiet(cpu, rsp, rdp, lastcomp);
-
/*
* Move callbacks from the outgoing CPU to the running CPU.
* Note that the outgoing CPU is now quiscent, so it is now
@@ -1457,20 +1441,7 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptable)
rnp = rnp->parent;
} while (rnp != NULL && !(rnp->qsmaskinit & mask));
- spin_unlock(&rsp->onofflock); /* irqs remain disabled. */
-
- /*
- * A new grace period might start here. If so, we will be part of
- * it, and its gpnum will be greater than ours, so we will
- * participate. It is also possible for the gpnum to have been
- * incremented before this function was called, and the bitmasks
- * to not be filled out until now, in which case we will also
- * participate due to our gpnum being behind.
- */
-
- /* Since it is coming online, the CPU is in a quiescent state. */
- cpu_quiet(cpu, rsp, rdp, lastcomp);
- local_irq_restore(flags);
+ spin_unlock_irqrestore(&rsp->onofflock, flags);
}
static void __cpuinit rcu_online_cpu(int cpu)
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index bf8a6f9f134..8e8287a983c 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -142,7 +142,7 @@ struct rcu_data {
*/
struct rcu_head *nxtlist;
struct rcu_head **nxttail[RCU_NEXT_SIZE];
- long qlen; /* # of queued callbacks */
+ long qlen; /* # of queued callbacks */
long blimit; /* Upper limit on a processed batch */
#ifdef CONFIG_NO_HZ
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index 47789369ea5..1cee04f627e 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -64,22 +64,31 @@ EXPORT_SYMBOL_GPL(rcu_batches_completed);
* not in a quiescent state. There might be any number of tasks blocked
* while in an RCU read-side critical section.
*/
-static void rcu_preempt_qs_record(int cpu)
+static void rcu_preempt_qs(int cpu)
{
struct rcu_data *rdp = &per_cpu(rcu_preempt_data, cpu);
- rdp->passed_quiesc = 1;
rdp->passed_quiesc_completed = rdp->completed;
+ barrier();
+ rdp->passed_quiesc = 1;
}
/*
- * We have entered the scheduler or are between softirqs in ksoftirqd.
- * If we are in an RCU read-side critical section, we need to reflect
- * that in the state of the rcu_node structure corresponding to this CPU.
- * Caller must disable hardirqs.
+ * We have entered the scheduler, and the current task might soon be
+ * context-switched away from. If this task is in an RCU read-side
+ * critical section, we will no longer be able to rely on the CPU to
+ * record that fact, so we enqueue the task on the appropriate entry
+ * of the blocked_tasks[] array. The task will dequeue itself when
+ * it exits the outermost enclosing RCU read-side critical section.
+ * Therefore, the current grace period cannot be permitted to complete
+ * until the blocked_tasks[] entry indexed by the low-order bit of
+ * rnp->gpnum empties.
+ *
+ * Caller must disable preemption.
*/
-static void rcu_preempt_qs(int cpu)
+static void rcu_preempt_note_context_switch(int cpu)
{
struct task_struct *t = current;
+ unsigned long flags;
int phase;
struct rcu_data *rdp;
struct rcu_node *rnp;
@@ -90,7 +99,7 @@ static void rcu_preempt_qs(int cpu)
/* Possibly blocking in an RCU read-side critical section. */
rdp = rcu_preempt_state.rda[cpu];
rnp = rdp->mynode;
- spin_lock(&rnp->lock);
+ spin_lock_irqsave(&rnp->lock, flags);
t->rcu_read_unlock_special |= RCU_READ_UNLOCK_BLOCKED;
t->rcu_blocked_node = rnp;
@@ -103,11 +112,15 @@ static void rcu_preempt_qs(int cpu)
* state for the current grace period), then as long
* as that task remains queued, the current grace period
* cannot end.
+ *
+ * But first, note that the current CPU must still be
+ * on line!
*/
- phase = !(rnp->qsmask & rdp->grpmask) ^ (rnp->gpnum & 0x1);
+ WARN_ON_ONCE((rdp->grpmask & rnp->qsmaskinit) == 0);
+ WARN_ON_ONCE(!list_empty(&t->rcu_node_entry));
+ phase = (rnp->gpnum + !(rnp->qsmask & rdp->grpmask)) & 0x1;
list_add(&t->rcu_node_entry, &rnp->blocked_tasks[phase]);
- smp_mb(); /* Ensure later ctxt swtch seen after above. */
- spin_unlock(&rnp->lock);
+ spin_unlock_irqrestore(&rnp->lock, flags);
}
/*
@@ -119,9 +132,10 @@ static void rcu_preempt_qs(int cpu)
* grace period, then the fact that the task has been enqueued
* means that we continue to block the current grace period.
*/
- rcu_preempt_qs_record(cpu);
- t->rcu_read_unlock_special &= ~(RCU_READ_UNLOCK_NEED_QS |
- RCU_READ_UNLOCK_GOT_QS);
+ rcu_preempt_qs(cpu);
+ local_irq_save(flags);
+ t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
+ local_irq_restore(flags);
}
/*
@@ -157,7 +171,7 @@ static void rcu_read_unlock_special(struct task_struct *t)
special = t->rcu_read_unlock_special;
if (special & RCU_READ_UNLOCK_NEED_QS) {
t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
- t->rcu_read_unlock_special |= RCU_READ_UNLOCK_GOT_QS;
+ rcu_preempt_qs(smp_processor_id());
}
/* Hardware IRQ handlers cannot block. */
@@ -177,10 +191,10 @@ static void rcu_read_unlock_special(struct task_struct *t)
*/
for (;;) {
rnp = t->rcu_blocked_node;
- spin_lock(&rnp->lock);
+ spin_lock(&rnp->lock); /* irqs already disabled. */
if (rnp == t->rcu_blocked_node)
break;
- spin_unlock(&rnp->lock);
+ spin_unlock(&rnp->lock); /* irqs remain disabled. */
}
empty = list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]);
list_del_init(&t->rcu_node_entry);
@@ -194,9 +208,8 @@ static void rcu_read_unlock_special(struct task_struct *t)
*/
if (!empty && rnp->qsmask == 0 &&
list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1])) {
- t->rcu_read_unlock_special &=
- ~(RCU_READ_UNLOCK_NEED_QS |
- RCU_READ_UNLOCK_GOT_QS);
+ struct rcu_node *rnp_p;
+
if (rnp->parent == NULL) {
/* Only one rcu_node in the tree. */
cpu_quiet_msk_finish(&rcu_preempt_state, flags);
@@ -205,9 +218,10 @@ static void rcu_read_unlock_special(struct task_struct *t)
/* Report up the rest of the hierarchy. */
mask = rnp->grpmask;
spin_unlock_irqrestore(&rnp->lock, flags);
- rnp = rnp->parent;
- spin_lock_irqsave(&rnp->lock, flags);
- cpu_quiet_msk(mask, &rcu_preempt_state, rnp, flags);
+ rnp_p = rnp->parent;
+ spin_lock_irqsave(&rnp_p->lock, flags);
+ WARN_ON_ONCE(rnp->qsmask);
+ cpu_quiet_msk(mask, &rcu_preempt_state, rnp_p, flags);
return;
}
spin_unlock(&rnp->lock);
@@ -259,6 +273,19 @@ static void rcu_print_task_stall(struct rcu_node *rnp)
#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
/*
+ * Check that the list of blocked tasks for the newly completed grace
+ * period is in fact empty. It is a serious bug to complete a grace
+ * period that still has RCU readers blocked! This function must be
+ * invoked -before- updating this rnp's ->gpnum, and the rnp's ->lock
+ * must be held by the caller.
+ */
+static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
+{
+ WARN_ON_ONCE(!list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]));
+ WARN_ON_ONCE(rnp->qsmask);
+}
+
+/*
* Check for preempted RCU readers for the specified rcu_node structure.
* If the caller needs a reliable answer, it must hold the rcu_node's
* >lock.
@@ -280,7 +307,8 @@ static int rcu_preempted_readers(struct rcu_node *rnp)
* The caller must hold rnp->lock with irqs disabled.
*/
static void rcu_preempt_offline_tasks(struct rcu_state *rsp,
- struct rcu_node *rnp)
+ struct rcu_node *rnp,
+ struct rcu_data *rdp)
{
int i;
struct list_head *lp;
@@ -292,6 +320,9 @@ static void rcu_preempt_offline_tasks(struct rcu_state *rsp,
WARN_ONCE(1, "Last CPU thought to be offlined?");
return; /* Shouldn't happen: at least one CPU online. */
}
+ WARN_ON_ONCE(rnp != rdp->mynode &&
+ (!list_empty(&rnp->blocked_tasks[0]) ||
+ !list_empty(&rnp->blocked_tasks[1])));
/*
* Move tasks up to root rcu_node. Rely on the fact that the
@@ -335,20 +366,12 @@ static void rcu_preempt_check_callbacks(int cpu)
struct task_struct *t = current;
if (t->rcu_read_lock_nesting == 0) {
- t->rcu_read_unlock_special &=
- ~(RCU_READ_UNLOCK_NEED_QS | RCU_READ_UNLOCK_GOT_QS);
- rcu_preempt_qs_record(cpu);
+ t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
+ rcu_preempt_qs(cpu);
return;
}
- if (per_cpu(rcu_preempt_data, cpu).qs_pending) {
- if (t->rcu_read_unlock_special & RCU_READ_UNLOCK_GOT_QS) {
- rcu_preempt_qs_record(cpu);
- t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_GOT_QS;
- } else if (!(t->rcu_read_unlock_special &
- RCU_READ_UNLOCK_NEED_QS)) {
- t->rcu_read_unlock_special |= RCU_READ_UNLOCK_NEED_QS;
- }
- }
+ if (per_cpu(rcu_preempt_data, cpu).qs_pending)
+ t->rcu_read_unlock_special |= RCU_READ_UNLOCK_NEED_QS;
}
/*
@@ -434,7 +457,7 @@ EXPORT_SYMBOL_GPL(rcu_batches_completed);
* Because preemptable RCU does not exist, we never have to check for
* CPUs being in quiescent states.
*/
-static void rcu_preempt_qs(int cpu)
+static void rcu_preempt_note_context_switch(int cpu)
{
}
@@ -451,6 +474,16 @@ static void rcu_print_task_stall(struct rcu_node *rnp)
#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
/*
+ * Because there is no preemptable RCU, there can be no readers blocked,
+ * so there is no need to check for blocked tasks. So check only for
+ * bogus qsmask values.
+ */
+static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
+{
+ WARN_ON_ONCE(rnp->qsmask);
+}
+
+/*
* Because preemptable RCU does not exist, there are never any preempted
* RCU readers.
*/
@@ -466,7 +499,8 @@ static int rcu_preempted_readers(struct rcu_node *rnp)
* tasks that were blocked within RCU read-side critical sections.
*/
static void rcu_preempt_offline_tasks(struct rcu_state *rsp,
- struct rcu_node *rnp)
+ struct rcu_node *rnp,
+ struct rcu_data *rdp)
{
}
diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c
index 0ea1bff6972..179e6ad80dc 100644
--- a/kernel/rcutree_trace.c
+++ b/kernel/rcutree_trace.c
@@ -20,7 +20,7 @@
* Papers: http://www.rdrop.com/users/paulmck/RCU
*
* For detailed explanation of Read-Copy Update mechanism see -
- * Documentation/RCU
+ * Documentation/RCU
*
*/
#include <linux/types.h>
@@ -93,7 +93,7 @@ static int rcudata_open(struct inode *inode, struct file *file)
return single_open(file, show_rcudata, NULL);
}
-static struct file_operations rcudata_fops = {
+static const struct file_operations rcudata_fops = {
.owner = THIS_MODULE,
.open = rcudata_open,
.read = seq_read,
@@ -145,7 +145,7 @@ static int rcudata_csv_open(struct inode *inode, struct file *file)
return single_open(file, show_rcudata_csv, NULL);
}
-static struct file_operations rcudata_csv_fops = {
+static const struct file_operations rcudata_csv_fops = {
.owner = THIS_MODULE,
.open = rcudata_csv_open,
.read = seq_read,
@@ -196,7 +196,7 @@ static int rcuhier_open(struct inode *inode, struct file *file)
return single_open(file, show_rcuhier, NULL);
}
-static struct file_operations rcuhier_fops = {
+static const struct file_operations rcuhier_fops = {
.owner = THIS_MODULE,
.open = rcuhier_open,
.read = seq_read,
@@ -222,7 +222,7 @@ static int rcugp_open(struct inode *inode, struct file *file)
return single_open(file, show_rcugp, NULL);
}
-static struct file_operations rcugp_fops = {
+static const struct file_operations rcugp_fops = {
.owner = THIS_MODULE,
.open = rcugp_open,
.read = seq_read,
@@ -276,7 +276,7 @@ static int rcu_pending_open(struct inode *inode, struct file *file)
return single_open(file, show_rcu_pending, NULL);
}
-static struct file_operations rcu_pending_fops = {
+static const struct file_operations rcu_pending_fops = {
.owner = THIS_MODULE,
.open = rcu_pending_open,
.read = seq_read,
diff --git a/kernel/relay.c b/kernel/relay.c
index bc188549788..760c26209a3 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -60,7 +60,7 @@ static int relay_buf_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
/*
* vm_ops for relay file mappings.
*/
-static struct vm_operations_struct relay_file_mmap_ops = {
+static const struct vm_operations_struct relay_file_mmap_ops = {
.fault = relay_buf_fault,
.close = relay_file_mmap_close,
};
diff --git a/kernel/res_counter.c b/kernel/res_counter.c
index e1338f07431..bcdabf37c40 100644
--- a/kernel/res_counter.c
+++ b/kernel/res_counter.c
@@ -19,6 +19,7 @@ void res_counter_init(struct res_counter *counter, struct res_counter *parent)
{
spin_lock_init(&counter->lock);
counter->limit = RESOURCE_MAX;
+ counter->soft_limit = RESOURCE_MAX;
counter->parent = parent;
}
@@ -101,6 +102,8 @@ res_counter_member(struct res_counter *counter, int member)
return &counter->limit;
case RES_FAILCNT:
return &counter->failcnt;
+ case RES_SOFT_LIMIT:
+ return &counter->soft_limit;
};
BUG();
diff --git a/kernel/resource.c b/kernel/resource.c
index 78b087221c1..fb11a58b959 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -223,13 +223,13 @@ int release_resource(struct resource *old)
EXPORT_SYMBOL(release_resource);
-#if defined(CONFIG_MEMORY_HOTPLUG) && !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
+#if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
/*
* Finds the lowest memory reosurce exists within [res->start.res->end)
- * the caller must specify res->start, res->end, res->flags.
+ * the caller must specify res->start, res->end, res->flags and "name".
* If found, returns 0, res is overwritten, if not found, returns -1.
*/
-static int find_next_system_ram(struct resource *res)
+static int find_next_system_ram(struct resource *res, char *name)
{
resource_size_t start, end;
struct resource *p;
@@ -245,6 +245,8 @@ static int find_next_system_ram(struct resource *res)
/* system ram is just marked as IORESOURCE_MEM */
if (p->flags != res->flags)
continue;
+ if (name && strcmp(p->name, name))
+ continue;
if (p->start > end) {
p = NULL;
break;
@@ -262,19 +264,26 @@ static int find_next_system_ram(struct resource *res)
res->end = p->end;
return 0;
}
-int
-walk_memory_resource(unsigned long start_pfn, unsigned long nr_pages, void *arg,
- int (*func)(unsigned long, unsigned long, void *))
+
+/*
+ * This function calls callback against all memory range of "System RAM"
+ * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY.
+ * Now, this function is only for "System RAM".
+ */
+int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
+ void *arg, int (*func)(unsigned long, unsigned long, void *))
{
struct resource res;
unsigned long pfn, len;
u64 orig_end;
int ret = -1;
+
res.start = (u64) start_pfn << PAGE_SHIFT;
res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
orig_end = res.end;
- while ((res.start < res.end) && (find_next_system_ram(&res) >= 0)) {
+ while ((res.start < res.end) &&
+ (find_next_system_ram(&res, "System RAM") >= 0)) {
pfn = (unsigned long)(res.start >> PAGE_SHIFT);
len = (unsigned long)((res.end + 1 - res.start) >> PAGE_SHIFT);
ret = (*func)(pfn, len, arg);
diff --git a/kernel/sched.c b/kernel/sched.c
index faf4d463bbf..1535f3884b8 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -39,7 +39,7 @@
#include <linux/completion.h>
#include <linux/kernel_stat.h>
#include <linux/debug_locks.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
#include <linux/security.h>
#include <linux/notifier.h>
#include <linux/profile.h>
@@ -681,15 +681,9 @@ inline void update_rq_clock(struct rq *rq)
* This interface allows printk to be called with the runqueue lock
* held and know whether or not it is OK to wake up the klogd.
*/
-int runqueue_is_locked(void)
+int runqueue_is_locked(int cpu)
{
- int cpu = get_cpu();
- struct rq *rq = cpu_rq(cpu);
- int ret;
-
- ret = spin_is_locked(&rq->lock);
- put_cpu();
- return ret;
+ return spin_is_locked(&cpu_rq(cpu)->lock);
}
/*
@@ -786,7 +780,7 @@ static int sched_feat_open(struct inode *inode, struct file *filp)
return single_open(filp, sched_feat_show, NULL);
}
-static struct file_operations sched_feat_fops = {
+static const struct file_operations sched_feat_fops = {
.open = sched_feat_open,
.write = sched_feat_write,
.read = seq_read,
@@ -2059,7 +2053,7 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
if (task_hot(p, old_rq->clock, NULL))
schedstat_inc(p, se.nr_forced2_migrations);
#endif
- perf_swcounter_event(PERF_COUNT_SW_CPU_MIGRATIONS,
+ perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS,
1, 1, NULL, 0);
}
p->se.vruntime -= old_cfsrq->min_vruntime -
@@ -2724,7 +2718,7 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
*/
prev_state = prev->state;
finish_arch_switch(prev);
- perf_counter_task_sched_in(current, cpu_of(rq));
+ perf_event_task_sched_in(current, cpu_of(rq));
finish_lock_switch(rq, prev);
fire_sched_in_preempt_notifiers(current);
@@ -2910,6 +2904,19 @@ unsigned long nr_iowait(void)
return sum;
}
+unsigned long nr_iowait_cpu(void)
+{
+ struct rq *this = this_rq();
+ return atomic_read(&this->nr_iowait);
+}
+
+unsigned long this_cpu_load(void)
+{
+ struct rq *this = this_rq();
+ return this->cpu_load[0];
+}
+
+
/* Variables and functions for calc_load */
static atomic_long_t calc_load_tasks;
static unsigned long calc_load_update;
@@ -5085,17 +5092,16 @@ void account_idle_time(cputime_t cputime)
*/
void account_process_tick(struct task_struct *p, int user_tick)
{
- cputime_t one_jiffy = jiffies_to_cputime(1);
- cputime_t one_jiffy_scaled = cputime_to_scaled(one_jiffy);
+ cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy);
struct rq *rq = this_rq();
if (user_tick)
- account_user_time(p, one_jiffy, one_jiffy_scaled);
+ account_user_time(p, cputime_one_jiffy, one_jiffy_scaled);
else if ((p != rq->idle) || (irq_count() != HARDIRQ_OFFSET))
- account_system_time(p, HARDIRQ_OFFSET, one_jiffy,
+ account_system_time(p, HARDIRQ_OFFSET, cputime_one_jiffy,
one_jiffy_scaled);
else
- account_idle_time(one_jiffy);
+ account_idle_time(cputime_one_jiffy);
}
/*
@@ -5199,7 +5205,7 @@ void scheduler_tick(void)
curr->sched_class->task_tick(rq, curr, 0);
spin_unlock(&rq->lock);
- perf_counter_task_tick(curr, cpu);
+ perf_event_task_tick(curr, cpu);
#ifdef CONFIG_SMP
rq->idle_at_tick = idle_cpu(cpu);
@@ -5415,7 +5421,7 @@ need_resched_nonpreemptible:
if (likely(prev != next)) {
sched_info_switch(prev, next);
- perf_counter_task_sched_out(prev, next, cpu);
+ perf_event_task_sched_out(prev, next, cpu);
rq->nr_switches++;
rq->curr = next;
@@ -6825,23 +6831,8 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
if (retval)
goto out_unlock;
- /*
- * Time slice is 0 for SCHED_FIFO tasks and for SCHED_OTHER
- * tasks that are on an otherwise idle runqueue:
- */
- time_slice = 0;
- if (p->policy == SCHED_RR) {
- time_slice = DEF_TIMESLICE;
- } else if (p->policy != SCHED_FIFO) {
- struct sched_entity *se = &p->se;
- unsigned long flags;
- struct rq *rq;
+ time_slice = p->sched_class->get_rr_interval(p);
- rq = task_rq_lock(p, &flags);
- if (rq->cfs.load.weight)
- time_slice = NS_TO_JIFFIES(sched_slice(&rq->cfs, se));
- task_rq_unlock(rq, &flags);
- }
read_unlock(&tasklist_lock);
jiffies_to_timespec(time_slice, &t);
retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
@@ -7692,7 +7683,7 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
/*
* Register at high priority so that task migration (migrate_all_tasks)
* happens before everything else. This has to be lower priority than
- * the notifier in the perf_counter subsystem, though.
+ * the notifier in the perf_event subsystem, though.
*/
static struct notifier_block __cpuinitdata migration_notifier = {
.notifier_call = migration_call,
@@ -9171,6 +9162,7 @@ void __init sched_init_smp(void)
cpumask_var_t non_isolated_cpus;
alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL);
+ alloc_cpumask_var(&fallback_doms, GFP_KERNEL);
#if defined(CONFIG_NUMA)
sched_group_nodes_bycpu = kzalloc(nr_cpu_ids * sizeof(void **),
@@ -9202,7 +9194,6 @@ void __init sched_init_smp(void)
sched_init_granularity();
free_cpumask_var(non_isolated_cpus);
- alloc_cpumask_var(&fallback_doms, GFP_KERNEL);
init_sched_rt_class();
}
#else
@@ -9549,7 +9540,7 @@ void __init sched_init(void)
alloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT);
#endif /* SMP */
- perf_counter_init();
+ perf_event_init();
scheduler_running = 1;
}
@@ -10321,7 +10312,7 @@ static int sched_rt_global_constraints(void)
#endif /* CONFIG_RT_GROUP_SCHED */
int sched_rt_handler(struct ctl_table *table, int write,
- struct file *filp, void __user *buffer, size_t *lenp,
+ void __user *buffer, size_t *lenp,
loff_t *ppos)
{
int ret;
@@ -10332,7 +10323,7 @@ int sched_rt_handler(struct ctl_table *table, int write,
old_period = sysctl_sched_rt_period;
old_runtime = sysctl_sched_rt_runtime;
- ret = proc_dointvec(table, write, filp, buffer, lenp, ppos);
+ ret = proc_dointvec(table, write, buffer, lenp, ppos);
if (!ret && write) {
ret = sched_rt_global_constraints();
@@ -10386,8 +10377,7 @@ cpu_cgroup_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp)
}
static int
-cpu_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
- struct task_struct *tsk)
+cpu_cgroup_can_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
{
#ifdef CONFIG_RT_GROUP_SCHED
if (!sched_rt_can_attach(cgroup_tg(cgrp), tsk))
@@ -10397,15 +10387,45 @@ cpu_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
if (tsk->sched_class != &fair_sched_class)
return -EINVAL;
#endif
+ return 0;
+}
+static int
+cpu_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
+ struct task_struct *tsk, bool threadgroup)
+{
+ int retval = cpu_cgroup_can_attach_task(cgrp, tsk);
+ if (retval)
+ return retval;
+ if (threadgroup) {
+ struct task_struct *c;
+ rcu_read_lock();
+ list_for_each_entry_rcu(c, &tsk->thread_group, thread_group) {
+ retval = cpu_cgroup_can_attach_task(cgrp, c);
+ if (retval) {
+ rcu_read_unlock();
+ return retval;
+ }
+ }
+ rcu_read_unlock();
+ }
return 0;
}
static void
cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
- struct cgroup *old_cont, struct task_struct *tsk)
+ struct cgroup *old_cont, struct task_struct *tsk,
+ bool threadgroup)
{
sched_move_task(tsk);
+ if (threadgroup) {
+ struct task_struct *c;
+ rcu_read_lock();
+ list_for_each_entry_rcu(c, &tsk->thread_group, thread_group) {
+ sched_move_task(c);
+ }
+ rcu_read_unlock();
+ }
}
#ifdef CONFIG_FAIR_GROUP_SCHED
diff --git a/kernel/sched_clock.c b/kernel/sched_clock.c
index e1d16c9a768..479ce5682d7 100644
--- a/kernel/sched_clock.c
+++ b/kernel/sched_clock.c
@@ -48,13 +48,6 @@ static __read_mostly int sched_clock_running;
__read_mostly int sched_clock_stable;
struct sched_clock_data {
- /*
- * Raw spinlock - this is a special case: this might be called
- * from within instrumentation code so we dont want to do any
- * instrumentation ourselves.
- */
- raw_spinlock_t lock;
-
u64 tick_raw;
u64 tick_gtod;
u64 clock;
@@ -80,7 +73,6 @@ void sched_clock_init(void)
for_each_possible_cpu(cpu) {
struct sched_clock_data *scd = cpu_sdc(cpu);
- scd->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
scd->tick_raw = 0;
scd->tick_gtod = ktime_now;
scd->clock = ktime_now;
@@ -109,14 +101,19 @@ static inline u64 wrap_max(u64 x, u64 y)
* - filter out backward motion
* - use the GTOD tick value to create a window to filter crazy TSC values
*/
-static u64 __update_sched_clock(struct sched_clock_data *scd, u64 now)
+static u64 sched_clock_local(struct sched_clock_data *scd)
{
- s64 delta = now - scd->tick_raw;
- u64 clock, min_clock, max_clock;
+ u64 now, clock, old_clock, min_clock, max_clock;
+ s64 delta;
+again:
+ now = sched_clock();
+ delta = now - scd->tick_raw;
if (unlikely(delta < 0))
delta = 0;
+ old_clock = scd->clock;
+
/*
* scd->clock = clamp(scd->tick_gtod + delta,
* max(scd->tick_gtod, scd->clock),
@@ -124,84 +121,73 @@ static u64 __update_sched_clock(struct sched_clock_data *scd, u64 now)
*/
clock = scd->tick_gtod + delta;
- min_clock = wrap_max(scd->tick_gtod, scd->clock);
- max_clock = wrap_max(scd->clock, scd->tick_gtod + TICK_NSEC);
+ min_clock = wrap_max(scd->tick_gtod, old_clock);
+ max_clock = wrap_max(old_clock, scd->tick_gtod + TICK_NSEC);
clock = wrap_max(clock, min_clock);
clock = wrap_min(clock, max_clock);
- scd->clock = clock;
+ if (cmpxchg64(&scd->clock, old_clock, clock) != old_clock)
+ goto again;
- return scd->clock;
+ return clock;
}
-static void lock_double_clock(struct sched_clock_data *data1,
- struct sched_clock_data *data2)
+static u64 sched_clock_remote(struct sched_clock_data *scd)
{
- if (data1 < data2) {
- __raw_spin_lock(&data1->lock);
- __raw_spin_lock(&data2->lock);
+ struct sched_clock_data *my_scd = this_scd();
+ u64 this_clock, remote_clock;
+ u64 *ptr, old_val, val;
+
+ sched_clock_local(my_scd);
+again:
+ this_clock = my_scd->clock;
+ remote_clock = scd->clock;
+
+ /*
+ * Use the opportunity that we have both locks
+ * taken to couple the two clocks: we take the
+ * larger time as the latest time for both
+ * runqueues. (this creates monotonic movement)
+ */
+ if (likely((s64)(remote_clock - this_clock) < 0)) {
+ ptr = &scd->clock;
+ old_val = remote_clock;
+ val = this_clock;
} else {
- __raw_spin_lock(&data2->lock);
- __raw_spin_lock(&data1->lock);
+ /*
+ * Should be rare, but possible:
+ */
+ ptr = &my_scd->clock;
+ old_val = this_clock;
+ val = remote_clock;
}
+
+ if (cmpxchg64(ptr, old_val, val) != old_val)
+ goto again;
+
+ return val;
}
u64 sched_clock_cpu(int cpu)
{
- u64 now, clock, this_clock, remote_clock;
struct sched_clock_data *scd;
+ u64 clock;
+
+ WARN_ON_ONCE(!irqs_disabled());
if (sched_clock_stable)
return sched_clock();
- scd = cpu_sdc(cpu);
-
- /*
- * Normally this is not called in NMI context - but if it is,
- * trying to do any locking here is totally lethal.
- */
- if (unlikely(in_nmi()))
- return scd->clock;
-
if (unlikely(!sched_clock_running))
return 0ull;
- WARN_ON_ONCE(!irqs_disabled());
- now = sched_clock();
-
- if (cpu != raw_smp_processor_id()) {
- struct sched_clock_data *my_scd = this_scd();
-
- lock_double_clock(scd, my_scd);
-
- this_clock = __update_sched_clock(my_scd, now);
- remote_clock = scd->clock;
-
- /*
- * Use the opportunity that we have both locks
- * taken to couple the two clocks: we take the
- * larger time as the latest time for both
- * runqueues. (this creates monotonic movement)
- */
- if (likely((s64)(remote_clock - this_clock) < 0)) {
- clock = this_clock;
- scd->clock = clock;
- } else {
- /*
- * Should be rare, but possible:
- */
- clock = remote_clock;
- my_scd->clock = remote_clock;
- }
-
- __raw_spin_unlock(&my_scd->lock);
- } else {
- __raw_spin_lock(&scd->lock);
- clock = __update_sched_clock(scd, now);
- }
+ scd = cpu_sdc(cpu);
- __raw_spin_unlock(&scd->lock);
+ if (cpu != smp_processor_id())
+ clock = sched_clock_remote(scd);
+ else
+ clock = sched_clock_local(scd);
return clock;
}
@@ -223,11 +209,9 @@ void sched_clock_tick(void)
now_gtod = ktime_to_ns(ktime_get());
now = sched_clock();
- __raw_spin_lock(&scd->lock);
scd->tick_raw = now;
scd->tick_gtod = now_gtod;
- __update_sched_clock(scd, now);
- __raw_spin_unlock(&scd->lock);
+ sched_clock_local(scd);
}
/*
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 10d218ab69f..4e777b47eed 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -384,10 +384,10 @@ static struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq)
#ifdef CONFIG_SCHED_DEBUG
int sched_nr_latency_handler(struct ctl_table *table, int write,
- struct file *filp, void __user *buffer, size_t *lenp,
+ void __user *buffer, size_t *lenp,
loff_t *ppos)
{
- int ret = proc_dointvec_minmax(table, write, filp, buffer, lenp, ppos);
+ int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
if (ret || !write)
return ret;
@@ -513,6 +513,7 @@ static void update_curr(struct cfs_rq *cfs_rq)
if (entity_is_task(curr)) {
struct task_struct *curtask = task_of(curr);
+ trace_sched_stat_runtime(curtask, delta_exec, curr->vruntime);
cpuacct_charge(curtask, delta_exec);
account_group_exec_runtime(curtask, delta_exec);
}
@@ -709,31 +710,28 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
if (initial && sched_feat(START_DEBIT))
vruntime += sched_vslice(cfs_rq, se);
- if (!initial) {
- /* sleeps upto a single latency don't count. */
- if (sched_feat(FAIR_SLEEPERS)) {
- unsigned long thresh = sysctl_sched_latency;
+ /* sleeps up to a single latency don't count. */
+ if (!initial && sched_feat(FAIR_SLEEPERS)) {
+ unsigned long thresh = sysctl_sched_latency;
- /*
- * Convert the sleeper threshold into virtual time.
- * SCHED_IDLE is a special sub-class. We care about
- * fairness only relative to other SCHED_IDLE tasks,
- * all of which have the same weight.
- */
- if (sched_feat(NORMALIZED_SLEEPER) &&
- (!entity_is_task(se) ||
- task_of(se)->policy != SCHED_IDLE))
- thresh = calc_delta_fair(thresh, se);
+ /*
+ * Convert the sleeper threshold into virtual time.
+ * SCHED_IDLE is a special sub-class. We care about
+ * fairness only relative to other SCHED_IDLE tasks,
+ * all of which have the same weight.
+ */
+ if (sched_feat(NORMALIZED_SLEEPER) && (!entity_is_task(se) ||
+ task_of(se)->policy != SCHED_IDLE))
+ thresh = calc_delta_fair(thresh, se);
- /*
- * Halve their sleep time's effect, to allow
- * for a gentler effect of sleepers:
- */
- if (sched_feat(GENTLE_FAIR_SLEEPERS))
- thresh >>= 1;
+ /*
+ * Halve their sleep time's effect, to allow
+ * for a gentler effect of sleepers:
+ */
+ if (sched_feat(GENTLE_FAIR_SLEEPERS))
+ thresh >>= 1;
- vruntime -= thresh;
- }
+ vruntime -= thresh;
}
/* ensure we never gain time by being placed backwards. */
@@ -1342,7 +1340,8 @@ static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flag
int sync = wake_flags & WF_SYNC;
if (sd_flag & SD_BALANCE_WAKE) {
- if (sched_feat(AFFINE_WAKEUPS))
+ if (sched_feat(AFFINE_WAKEUPS) &&
+ cpumask_test_cpu(cpu, &p->cpus_allowed))
want_affine = 1;
new_cpu = prev_cpu;
}
@@ -1940,6 +1939,25 @@ static void moved_group_fair(struct task_struct *p)
}
#endif
+unsigned int get_rr_interval_fair(struct task_struct *task)
+{
+ struct sched_entity *se = &task->se;
+ unsigned long flags;
+ struct rq *rq;
+ unsigned int rr_interval = 0;
+
+ /*
+ * Time slice is 0 for SCHED_OTHER tasks that are on an otherwise
+ * idle runqueue:
+ */
+ rq = task_rq_lock(task, &flags);
+ if (rq->cfs.load.weight)
+ rr_interval = NS_TO_JIFFIES(sched_slice(&rq->cfs, se));
+ task_rq_unlock(rq, &flags);
+
+ return rr_interval;
+}
+
/*
* All the scheduling class methods:
*/
@@ -1968,6 +1986,8 @@ static const struct sched_class fair_sched_class = {
.prio_changed = prio_changed_fair,
.switched_to = switched_to_fair,
+ .get_rr_interval = get_rr_interval_fair,
+
#ifdef CONFIG_FAIR_GROUP_SCHED
.moved_group = moved_group_fair,
#endif
diff --git a/kernel/sched_idletask.c b/kernel/sched_idletask.c
index a8b448af004..b133a28fcde 100644
--- a/kernel/sched_idletask.c
+++ b/kernel/sched_idletask.c
@@ -97,6 +97,11 @@ static void prio_changed_idle(struct rq *rq, struct task_struct *p,
check_preempt_curr(rq, p, 0);
}
+unsigned int get_rr_interval_idle(struct task_struct *task)
+{
+ return 0;
+}
+
/*
* Simple, special scheduling class for the per-CPU idle tasks:
*/
@@ -122,6 +127,8 @@ static const struct sched_class idle_sched_class = {
.set_curr_task = set_curr_task_idle,
.task_tick = task_tick_idle,
+ .get_rr_interval = get_rr_interval_idle,
+
.prio_changed = prio_changed_idle,
.switched_to = switched_to_idle,
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 13de7126a6a..a4d790cddb1 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -1734,6 +1734,17 @@ static void set_curr_task_rt(struct rq *rq)
dequeue_pushable_task(rq, p);
}
+unsigned int get_rr_interval_rt(struct task_struct *task)
+{
+ /*
+ * Time slice is 0 for SCHED_FIFO tasks
+ */
+ if (task->policy == SCHED_RR)
+ return DEF_TIMESLICE;
+ else
+ return 0;
+}
+
static const struct sched_class rt_sched_class = {
.next = &fair_sched_class,
.enqueue_task = enqueue_task_rt,
@@ -1762,6 +1773,8 @@ static const struct sched_class rt_sched_class = {
.set_curr_task = set_curr_task_rt,
.task_tick = task_tick_rt,
+ .get_rr_interval = get_rr_interval_rt,
+
.prio_changed = prio_changed_rt,
.switched_to = switched_to_rt,
};
diff --git a/kernel/signal.c b/kernel/signal.c
index 64c5deeaca5..6705320784f 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -705,7 +705,7 @@ static int prepare_signal(int sig, struct task_struct *p, int from_ancestor_ns)
if (why) {
/*
- * The first thread which returns from finish_stop()
+ * The first thread which returns from do_signal_stop()
* will take ->siglock, notice SIGNAL_CLD_MASK, and
* notify its parent. See get_signal_to_deliver().
*/
@@ -971,6 +971,20 @@ specific_send_sig_info(int sig, struct siginfo *info, struct task_struct *t)
return send_signal(sig, info, t, 0);
}
+int do_send_sig_info(int sig, struct siginfo *info, struct task_struct *p,
+ bool group)
+{
+ unsigned long flags;
+ int ret = -ESRCH;
+
+ if (lock_task_sighand(p, &flags)) {
+ ret = send_signal(sig, info, p, group);
+ unlock_task_sighand(p, &flags);
+ }
+
+ return ret;
+}
+
/*
* Force a signal that the process can't ignore: if necessary
* we unblock the signal and change any SIG_IGN to SIG_DFL.
@@ -1036,12 +1050,6 @@ void zap_other_threads(struct task_struct *p)
}
}
-int __fatal_signal_pending(struct task_struct *tsk)
-{
- return sigismember(&tsk->pending.signal, SIGKILL);
-}
-EXPORT_SYMBOL(__fatal_signal_pending);
-
struct sighand_struct *lock_task_sighand(struct task_struct *tsk, unsigned long *flags)
{
struct sighand_struct *sighand;
@@ -1068,18 +1076,10 @@ struct sighand_struct *lock_task_sighand(struct task_struct *tsk, unsigned long
*/
int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p)
{
- unsigned long flags;
- int ret;
+ int ret = check_kill_permission(sig, info, p);
- ret = check_kill_permission(sig, info, p);
-
- if (!ret && sig) {
- ret = -ESRCH;
- if (lock_task_sighand(p, &flags)) {
- ret = __group_send_sig_info(sig, info, p);
- unlock_task_sighand(p, &flags);
- }
- }
+ if (!ret && sig)
+ ret = do_send_sig_info(sig, info, p, true);
return ret;
}
@@ -1224,15 +1224,9 @@ static int kill_something_info(int sig, struct siginfo *info, pid_t pid)
* These are for backward compatibility with the rest of the kernel source.
*/
-/*
- * The caller must ensure the task can't exit.
- */
int
send_sig_info(int sig, struct siginfo *info, struct task_struct *p)
{
- int ret;
- unsigned long flags;
-
/*
* Make sure legacy kernel users don't send in bad values
* (normal paths check this in check_kill_permission).
@@ -1240,10 +1234,7 @@ send_sig_info(int sig, struct siginfo *info, struct task_struct *p)
if (!valid_signal(sig))
return -EINVAL;
- spin_lock_irqsave(&p->sighand->siglock, flags);
- ret = specific_send_sig_info(sig, info, p);
- spin_unlock_irqrestore(&p->sighand->siglock, flags);
- return ret;
+ return do_send_sig_info(sig, info, p, false);
}
#define __si_special(priv) \
@@ -1383,15 +1374,6 @@ ret:
}
/*
- * Wake up any threads in the parent blocked in wait* syscalls.
- */
-static inline void __wake_up_parent(struct task_struct *p,
- struct task_struct *parent)
-{
- wake_up_interruptible_sync(&parent->signal->wait_chldexit);
-}
-
-/*
* Let a parent know about the death of a child.
* For a stopped/continued status change, use do_notify_parent_cldstop instead.
*
@@ -1673,29 +1655,6 @@ void ptrace_notify(int exit_code)
spin_unlock_irq(&current->sighand->siglock);
}
-static void
-finish_stop(int stop_count)
-{
- /*
- * If there are no other threads in the group, or if there is
- * a group stop in progress and we are the last to stop,
- * report to the parent. When ptraced, every thread reports itself.
- */
- if (tracehook_notify_jctl(stop_count == 0, CLD_STOPPED)) {
- read_lock(&tasklist_lock);
- do_notify_parent_cldstop(current, CLD_STOPPED);
- read_unlock(&tasklist_lock);
- }
-
- do {
- schedule();
- } while (try_to_freeze());
- /*
- * Now we don't run again until continued.
- */
- current->exit_code = 0;
-}
-
/*
* This performs the stopping for SIGSTOP and other stop signals.
* We have to stop all threads in the thread group.
@@ -1705,15 +1664,9 @@ finish_stop(int stop_count)
static int do_signal_stop(int signr)
{
struct signal_struct *sig = current->signal;
- int stop_count;
+ int notify;
- if (sig->group_stop_count > 0) {
- /*
- * There is a group stop in progress. We don't need to
- * start another one.
- */
- stop_count = --sig->group_stop_count;
- } else {
+ if (!sig->group_stop_count) {
struct task_struct *t;
if (!likely(sig->flags & SIGNAL_STOP_DEQUEUED) ||
@@ -1725,7 +1678,7 @@ static int do_signal_stop(int signr)
*/
sig->group_exit_code = signr;
- stop_count = 0;
+ sig->group_stop_count = 1;
for (t = next_thread(current); t != current; t = next_thread(t))
/*
* Setting state to TASK_STOPPED for a group
@@ -1734,19 +1687,44 @@ static int do_signal_stop(int signr)
*/
if (!(t->flags & PF_EXITING) &&
!task_is_stopped_or_traced(t)) {
- stop_count++;
+ sig->group_stop_count++;
signal_wake_up(t, 0);
}
- sig->group_stop_count = stop_count;
}
+ /*
+ * If there are no other threads in the group, or if there is
+ * a group stop in progress and we are the last to stop, report
+ * to the parent. When ptraced, every thread reports itself.
+ */
+ notify = sig->group_stop_count == 1 ? CLD_STOPPED : 0;
+ notify = tracehook_notify_jctl(notify, CLD_STOPPED);
+ /*
+ * tracehook_notify_jctl() can drop and reacquire siglock, so
+ * we keep ->group_stop_count != 0 before the call. If SIGCONT
+ * or SIGKILL comes in between ->group_stop_count == 0.
+ */
+ if (sig->group_stop_count) {
+ if (!--sig->group_stop_count)
+ sig->flags = SIGNAL_STOP_STOPPED;
+ current->exit_code = sig->group_exit_code;
+ __set_current_state(TASK_STOPPED);
+ }
+ spin_unlock_irq(&current->sighand->siglock);
- if (stop_count == 0)
- sig->flags = SIGNAL_STOP_STOPPED;
- current->exit_code = sig->group_exit_code;
- __set_current_state(TASK_STOPPED);
+ if (notify) {
+ read_lock(&tasklist_lock);
+ do_notify_parent_cldstop(current, notify);
+ read_unlock(&tasklist_lock);
+ }
+
+ /* Now we don't run again until woken by SIGCONT or SIGKILL */
+ do {
+ schedule();
+ } while (try_to_freeze());
+
+ tracehook_finish_jctl();
+ current->exit_code = 0;
- spin_unlock_irq(&current->sighand->siglock);
- finish_stop(stop_count);
return 1;
}
@@ -1815,14 +1793,15 @@ relock:
int why = (signal->flags & SIGNAL_STOP_CONTINUED)
? CLD_CONTINUED : CLD_STOPPED;
signal->flags &= ~SIGNAL_CLD_MASK;
- spin_unlock_irq(&sighand->siglock);
- if (unlikely(!tracehook_notify_jctl(1, why)))
- goto relock;
+ why = tracehook_notify_jctl(why, CLD_CONTINUED);
+ spin_unlock_irq(&sighand->siglock);
- read_lock(&tasklist_lock);
- do_notify_parent_cldstop(current->group_leader, why);
- read_unlock(&tasklist_lock);
+ if (why) {
+ read_lock(&tasklist_lock);
+ do_notify_parent_cldstop(current->group_leader, why);
+ read_unlock(&tasklist_lock);
+ }
goto relock;
}
@@ -1987,14 +1966,14 @@ void exit_signals(struct task_struct *tsk)
if (unlikely(tsk->signal->group_stop_count) &&
!--tsk->signal->group_stop_count) {
tsk->signal->flags = SIGNAL_STOP_STOPPED;
- group_stop = 1;
+ group_stop = tracehook_notify_jctl(CLD_STOPPED, CLD_STOPPED);
}
out:
spin_unlock_irq(&tsk->sighand->siglock);
- if (unlikely(group_stop) && tracehook_notify_jctl(1, CLD_STOPPED)) {
+ if (unlikely(group_stop)) {
read_lock(&tasklist_lock);
- do_notify_parent_cldstop(tsk, CLD_STOPPED);
+ do_notify_parent_cldstop(tsk, group_stop);
read_unlock(&tasklist_lock);
}
}
@@ -2290,7 +2269,6 @@ static int
do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info)
{
struct task_struct *p;
- unsigned long flags;
int error = -ESRCH;
rcu_read_lock();
@@ -2300,14 +2278,16 @@ do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info)
/*
* The null signal is a permissions and process existence
* probe. No signal is actually delivered.
- *
- * If lock_task_sighand() fails we pretend the task dies
- * after receiving the signal. The window is tiny, and the
- * signal is private anyway.
*/
- if (!error && sig && lock_task_sighand(p, &flags)) {
- error = specific_send_sig_info(sig, info, p);
- unlock_task_sighand(p, &flags);
+ if (!error && sig) {
+ error = do_send_sig_info(sig, info, p, false);
+ /*
+ * If lock_task_sighand() failed we pretend the task
+ * dies after receiving the signal. The window is tiny,
+ * and the signal is private anyway.
+ */
+ if (unlikely(error == -ESRCH))
+ error = 0;
}
}
rcu_read_unlock();
diff --git a/kernel/slow-work.c b/kernel/slow-work.c
index 09d7519557d..0d31135efbf 100644
--- a/kernel/slow-work.c
+++ b/kernel/slow-work.c
@@ -26,10 +26,10 @@ static void slow_work_cull_timeout(unsigned long);
static void slow_work_oom_timeout(unsigned long);
#ifdef CONFIG_SYSCTL
-static int slow_work_min_threads_sysctl(struct ctl_table *, int, struct file *,
+static int slow_work_min_threads_sysctl(struct ctl_table *, int,
void __user *, size_t *, loff_t *);
-static int slow_work_max_threads_sysctl(struct ctl_table *, int , struct file *,
+static int slow_work_max_threads_sysctl(struct ctl_table *, int ,
void __user *, size_t *, loff_t *);
#endif
@@ -493,10 +493,10 @@ static void slow_work_oom_timeout(unsigned long data)
* Handle adjustment of the minimum number of threads
*/
static int slow_work_min_threads_sysctl(struct ctl_table *table, int write,
- struct file *filp, void __user *buffer,
+ void __user *buffer,
size_t *lenp, loff_t *ppos)
{
- int ret = proc_dointvec_minmax(table, write, filp, buffer, lenp, ppos);
+ int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
int n;
if (ret == 0) {
@@ -521,10 +521,10 @@ static int slow_work_min_threads_sysctl(struct ctl_table *table, int write,
* Handle adjustment of the maximum number of threads
*/
static int slow_work_max_threads_sysctl(struct ctl_table *table, int write,
- struct file *filp, void __user *buffer,
+ void __user *buffer,
size_t *lenp, loff_t *ppos)
{
- int ret = proc_dointvec_minmax(table, write, filp, buffer, lenp, ppos);
+ int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
int n;
if (ret == 0) {
diff --git a/kernel/smp.c b/kernel/smp.c
index 8e218500ab1..c9d1c7835c2 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -29,8 +29,7 @@ enum {
struct call_function_data {
struct call_single_data csd;
- spinlock_t lock;
- unsigned int refs;
+ atomic_t refs;
cpumask_var_t cpumask;
};
@@ -39,9 +38,7 @@ struct call_single_queue {
spinlock_t lock;
};
-static DEFINE_PER_CPU(struct call_function_data, cfd_data) = {
- .lock = __SPIN_LOCK_UNLOCKED(cfd_data.lock),
-};
+static DEFINE_PER_CPU(struct call_function_data, cfd_data);
static int
hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
@@ -196,25 +193,18 @@ void generic_smp_call_function_interrupt(void)
list_for_each_entry_rcu(data, &call_function.queue, csd.list) {
int refs;
- spin_lock(&data->lock);
- if (!cpumask_test_cpu(cpu, data->cpumask)) {
- spin_unlock(&data->lock);
+ if (!cpumask_test_and_clear_cpu(cpu, data->cpumask))
continue;
- }
- cpumask_clear_cpu(cpu, data->cpumask);
- spin_unlock(&data->lock);
data->csd.func(data->csd.info);
- spin_lock(&data->lock);
- WARN_ON(data->refs == 0);
- refs = --data->refs;
+ refs = atomic_dec_return(&data->refs);
+ WARN_ON(refs < 0);
if (!refs) {
spin_lock(&call_function.lock);
list_del_rcu(&data->csd.list);
spin_unlock(&call_function.lock);
}
- spin_unlock(&data->lock);
if (refs)
continue;
@@ -357,13 +347,6 @@ void __smp_call_function_single(int cpu, struct call_single_data *data,
generic_exec_single(cpu, data, wait);
}
-/* Deprecated: shim for archs using old arch_send_call_function_ipi API. */
-
-#ifndef arch_send_call_function_ipi_mask
-# define arch_send_call_function_ipi_mask(maskp) \
- arch_send_call_function_ipi(*(maskp))
-#endif
-
/**
* smp_call_function_many(): Run a function on a set of other CPUs.
* @mask: The set of cpus to run on (only runs on online subset).
@@ -419,23 +402,20 @@ void smp_call_function_many(const struct cpumask *mask,
data = &__get_cpu_var(cfd_data);
csd_lock(&data->csd);
- spin_lock_irqsave(&data->lock, flags);
data->csd.func = func;
data->csd.info = info;
cpumask_and(data->cpumask, mask, cpu_online_mask);
cpumask_clear_cpu(this_cpu, data->cpumask);
- data->refs = cpumask_weight(data->cpumask);
+ atomic_set(&data->refs, cpumask_weight(data->cpumask));
- spin_lock(&call_function.lock);
+ spin_lock_irqsave(&call_function.lock, flags);
/*
* Place entry at the _HEAD_ of the list, so that any cpu still
* observing the entry in generic_smp_call_function_interrupt()
* will not miss any other list entries:
*/
list_add_rcu(&data->csd.list, &call_function.queue);
- spin_unlock(&call_function.lock);
-
- spin_unlock_irqrestore(&data->lock, flags);
+ spin_unlock_irqrestore(&call_function.lock, flags);
/*
* Make the list addition visible before sending the ipi.
diff --git a/kernel/softlockup.c b/kernel/softlockup.c
index 88796c33083..81324d12eb3 100644
--- a/kernel/softlockup.c
+++ b/kernel/softlockup.c
@@ -90,11 +90,11 @@ void touch_all_softlockup_watchdogs(void)
EXPORT_SYMBOL(touch_all_softlockup_watchdogs);
int proc_dosoftlockup_thresh(struct ctl_table *table, int write,
- struct file *filp, void __user *buffer,
+ void __user *buffer,
size_t *lenp, loff_t *ppos)
{
touch_all_softlockup_watchdogs();
- return proc_dointvec_minmax(table, write, filp, buffer, lenp, ppos);
+ return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
}
/*
diff --git a/kernel/sys.c b/kernel/sys.c
index b3f1097c76f..255475d163e 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -14,7 +14,7 @@
#include <linux/prctl.h>
#include <linux/highuid.h>
#include <linux/fs.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
#include <linux/resource.h>
#include <linux/kernel.h>
#include <linux/kexec.h>
@@ -1338,6 +1338,7 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
unsigned long flags;
cputime_t utime, stime;
struct task_cputime cputime;
+ unsigned long maxrss = 0;
memset((char *) r, 0, sizeof *r);
utime = stime = cputime_zero;
@@ -1346,6 +1347,7 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
utime = task_utime(current);
stime = task_stime(current);
accumulate_thread_rusage(p, r);
+ maxrss = p->signal->maxrss;
goto out;
}
@@ -1363,6 +1365,7 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
r->ru_majflt = p->signal->cmaj_flt;
r->ru_inblock = p->signal->cinblock;
r->ru_oublock = p->signal->coublock;
+ maxrss = p->signal->cmaxrss;
if (who == RUSAGE_CHILDREN)
break;
@@ -1377,6 +1380,8 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
r->ru_majflt += p->signal->maj_flt;
r->ru_inblock += p->signal->inblock;
r->ru_oublock += p->signal->oublock;
+ if (maxrss < p->signal->maxrss)
+ maxrss = p->signal->maxrss;
t = p;
do {
accumulate_thread_rusage(t, r);
@@ -1392,6 +1397,15 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
out:
cputime_to_timeval(utime, &r->ru_utime);
cputime_to_timeval(stime, &r->ru_stime);
+
+ if (who != RUSAGE_CHILDREN) {
+ struct mm_struct *mm = get_task_mm(p);
+ if (mm) {
+ setmax_mm_hiwater_rss(&maxrss, mm);
+ mmput(mm);
+ }
+ }
+ r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */
}
int getrusage(struct task_struct *p, int who, struct rusage __user *ru)
@@ -1511,11 +1525,11 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
case PR_SET_TSC:
error = SET_TSC_CTL(arg2);
break;
- case PR_TASK_PERF_COUNTERS_DISABLE:
- error = perf_counter_task_disable();
+ case PR_TASK_PERF_EVENTS_DISABLE:
+ error = perf_event_task_disable();
break;
- case PR_TASK_PERF_COUNTERS_ENABLE:
- error = perf_counter_task_enable();
+ case PR_TASK_PERF_EVENTS_ENABLE:
+ error = perf_event_task_enable();
break;
case PR_GET_TIMERSLACK:
error = current->timer_slack_ns;
@@ -1528,6 +1542,28 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
current->timer_slack_ns = arg2;
error = 0;
break;
+ case PR_MCE_KILL:
+ if (arg4 | arg5)
+ return -EINVAL;
+ switch (arg2) {
+ case 0:
+ if (arg3 != 0)
+ return -EINVAL;
+ current->flags &= ~PF_MCE_PROCESS;
+ break;
+ case 1:
+ current->flags |= PF_MCE_PROCESS;
+ if (arg3 != 0)
+ current->flags |= PF_MCE_EARLY;
+ else
+ current->flags &= ~PF_MCE_EARLY;
+ break;
+ default:
+ return -EINVAL;
+ }
+ error = 0;
+ break;
+
default:
error = -EINVAL;
break;
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 68320f6b07b..e06d0b8d195 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -49,6 +49,7 @@ cond_syscall(sys_sendmsg);
cond_syscall(compat_sys_sendmsg);
cond_syscall(sys_recvmsg);
cond_syscall(compat_sys_recvmsg);
+cond_syscall(compat_sys_recvfrom);
cond_syscall(sys_socketcall);
cond_syscall(sys_futex);
cond_syscall(compat_sys_futex);
@@ -177,4 +178,4 @@ cond_syscall(sys_eventfd);
cond_syscall(sys_eventfd2);
/* performance counters: */
-cond_syscall(sys_perf_counter_open);
+cond_syscall(sys_perf_event_open);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 1a631ba684a..0d949c51741 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -26,7 +26,6 @@
#include <linux/proc_fs.h>
#include <linux/security.h>
#include <linux/ctype.h>
-#include <linux/utsname.h>
#include <linux/kmemcheck.h>
#include <linux/smp_lock.h>
#include <linux/fs.h>
@@ -50,7 +49,7 @@
#include <linux/reboot.h>
#include <linux/ftrace.h>
#include <linux/slow-work.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
#include <asm/uaccess.h>
#include <asm/processor.h>
@@ -77,6 +76,7 @@ extern int max_threads;
extern int core_uses_pid;
extern int suid_dumpable;
extern char core_pattern[];
+extern unsigned int core_pipe_limit;
extern int pid_max;
extern int min_free_kbytes;
extern int pid_max_min, pid_max_max;
@@ -106,6 +106,9 @@ static int __maybe_unused one = 1;
static int __maybe_unused two = 2;
static unsigned long one_ul = 1;
static int one_hundred = 100;
+#ifdef CONFIG_PRINTK
+static int ten_thousand = 10000;
+#endif
/* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
@@ -160,9 +163,9 @@ extern int max_lock_depth;
#endif
#ifdef CONFIG_PROC_SYSCTL
-static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
+static int proc_do_cad_pid(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos);
-static int proc_taint(struct ctl_table *table, int write, struct file *filp,
+static int proc_taint(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos);
#endif
@@ -421,6 +424,14 @@ static struct ctl_table kern_table[] = {
.proc_handler = &proc_dostring,
.strategy = &sysctl_string,
},
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "core_pipe_limit",
+ .data = &core_pipe_limit,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ },
#ifdef CONFIG_PROC_SYSCTL
{
.procname = "tainted",
@@ -722,6 +733,17 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = &proc_dointvec,
},
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "printk_delay",
+ .data = &printk_delay_msec,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec_minmax,
+ .strategy = &sysctl_intvec,
+ .extra1 = &zero,
+ .extra2 = &ten_thousand,
+ },
#endif
{
.ctl_name = KERN_NGROUPS_MAX,
@@ -964,28 +986,28 @@ static struct ctl_table kern_table[] = {
.child = slow_work_sysctls,
},
#endif
-#ifdef CONFIG_PERF_COUNTERS
+#ifdef CONFIG_PERF_EVENTS
{
.ctl_name = CTL_UNNUMBERED,
- .procname = "perf_counter_paranoid",
- .data = &sysctl_perf_counter_paranoid,
- .maxlen = sizeof(sysctl_perf_counter_paranoid),
+ .procname = "perf_event_paranoid",
+ .data = &sysctl_perf_event_paranoid,
+ .maxlen = sizeof(sysctl_perf_event_paranoid),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
- .procname = "perf_counter_mlock_kb",
- .data = &sysctl_perf_counter_mlock,
- .maxlen = sizeof(sysctl_perf_counter_mlock),
+ .procname = "perf_event_mlock_kb",
+ .data = &sysctl_perf_event_mlock,
+ .maxlen = sizeof(sysctl_perf_event_mlock),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
- .procname = "perf_counter_max_sample_rate",
- .data = &sysctl_perf_counter_sample_rate,
- .maxlen = sizeof(sysctl_perf_counter_sample_rate),
+ .procname = "perf_event_max_sample_rate",
+ .data = &sysctl_perf_event_sample_rate,
+ .maxlen = sizeof(sysctl_perf_event_sample_rate),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
@@ -1376,6 +1398,31 @@ static struct ctl_table vm_table[] = {
.mode = 0644,
.proc_handler = &scan_unevictable_handler,
},
+#ifdef CONFIG_MEMORY_FAILURE
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "memory_failure_early_kill",
+ .data = &sysctl_memory_failure_early_kill,
+ .maxlen = sizeof(sysctl_memory_failure_early_kill),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec_minmax,
+ .strategy = &sysctl_intvec,
+ .extra1 = &zero,
+ .extra2 = &one,
+ },
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "memory_failure_recovery",
+ .data = &sysctl_memory_failure_recovery,
+ .maxlen = sizeof(sysctl_memory_failure_recovery),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec_minmax,
+ .strategy = &sysctl_intvec,
+ .extra1 = &zero,
+ .extra2 = &one,
+ },
+#endif
+
/*
* NOTE: do not add new entries to this table unless you have read
* Documentation/sysctl/ctl_unnumbered.txt
@@ -2204,7 +2251,7 @@ void sysctl_head_put(struct ctl_table_header *head)
#ifdef CONFIG_PROC_SYSCTL
static int _proc_do_string(void* data, int maxlen, int write,
- struct file *filp, void __user *buffer,
+ void __user *buffer,
size_t *lenp, loff_t *ppos)
{
size_t len;
@@ -2265,7 +2312,6 @@ static int _proc_do_string(void* data, int maxlen, int write,
* proc_dostring - read a string sysctl
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
- * @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
@@ -2279,10 +2325,10 @@ static int _proc_do_string(void* data, int maxlen, int write,
*
* Returns 0 on success.
*/
-int proc_dostring(struct ctl_table *table, int write, struct file *filp,
+int proc_dostring(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
- return _proc_do_string(table->data, table->maxlen, write, filp,
+ return _proc_do_string(table->data, table->maxlen, write,
buffer, lenp, ppos);
}
@@ -2307,7 +2353,7 @@ static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
}
static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
- int write, struct file *filp, void __user *buffer,
+ int write, void __user *buffer,
size_t *lenp, loff_t *ppos,
int (*conv)(int *negp, unsigned long *lvalp, int *valp,
int write, void *data),
@@ -2414,13 +2460,13 @@ static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
#undef TMPBUFLEN
}
-static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
+static int do_proc_dointvec(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos,
int (*conv)(int *negp, unsigned long *lvalp, int *valp,
int write, void *data),
void *data)
{
- return __do_proc_dointvec(table->data, table, write, filp,
+ return __do_proc_dointvec(table->data, table, write,
buffer, lenp, ppos, conv, data);
}
@@ -2428,7 +2474,6 @@ static int do_proc_dointvec(struct ctl_table *table, int write, struct file *fil
* proc_dointvec - read a vector of integers
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
- * @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
@@ -2438,10 +2483,10 @@ static int do_proc_dointvec(struct ctl_table *table, int write, struct file *fil
*
* Returns 0 on success.
*/
-int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
+int proc_dointvec(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
- return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
+ return do_proc_dointvec(table,write,buffer,lenp,ppos,
NULL,NULL);
}
@@ -2449,7 +2494,7 @@ int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
* Taint values can only be increased
* This means we can safely use a temporary.
*/
-static int proc_taint(struct ctl_table *table, int write, struct file *filp,
+static int proc_taint(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
struct ctl_table t;
@@ -2461,7 +2506,7 @@ static int proc_taint(struct ctl_table *table, int write, struct file *filp,
t = *table;
t.data = &tmptaint;
- err = proc_doulongvec_minmax(&t, write, filp, buffer, lenp, ppos);
+ err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
if (err < 0)
return err;
@@ -2513,7 +2558,6 @@ static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
* proc_dointvec_minmax - read a vector of integers with min/max values
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
- * @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
@@ -2526,19 +2570,18 @@ static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
*
* Returns 0 on success.
*/
-int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
+int proc_dointvec_minmax(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
struct do_proc_dointvec_minmax_conv_param param = {
.min = (int *) table->extra1,
.max = (int *) table->extra2,
};
- return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
+ return do_proc_dointvec(table, write, buffer, lenp, ppos,
do_proc_dointvec_minmax_conv, &param);
}
static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
- struct file *filp,
void __user *buffer,
size_t *lenp, loff_t *ppos,
unsigned long convmul,
@@ -2643,21 +2686,19 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int
}
static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
- struct file *filp,
void __user *buffer,
size_t *lenp, loff_t *ppos,
unsigned long convmul,
unsigned long convdiv)
{
return __do_proc_doulongvec_minmax(table->data, table, write,
- filp, buffer, lenp, ppos, convmul, convdiv);
+ buffer, lenp, ppos, convmul, convdiv);
}
/**
* proc_doulongvec_minmax - read a vector of long integers with min/max values
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
- * @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
@@ -2670,17 +2711,16 @@ static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
*
* Returns 0 on success.
*/
-int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
+int proc_doulongvec_minmax(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
- return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
+ return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
}
/**
* proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
- * @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
@@ -2695,11 +2735,10 @@ int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp
* Returns 0 on success.
*/
int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
- struct file *filp,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
- return do_proc_doulongvec_minmax(table, write, filp, buffer,
+ return do_proc_doulongvec_minmax(table, write, buffer,
lenp, ppos, HZ, 1000l);
}
@@ -2775,7 +2814,6 @@ static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
* proc_dointvec_jiffies - read a vector of integers as seconds
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
- * @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
@@ -2787,10 +2825,10 @@ static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
*
* Returns 0 on success.
*/
-int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
+int proc_dointvec_jiffies(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
- return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
+ return do_proc_dointvec(table,write,buffer,lenp,ppos,
do_proc_dointvec_jiffies_conv,NULL);
}
@@ -2798,7 +2836,6 @@ int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
* proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
- * @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: pointer to the file position
@@ -2810,10 +2847,10 @@ int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
*
* Returns 0 on success.
*/
-int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
+int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
- return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
+ return do_proc_dointvec(table,write,buffer,lenp,ppos,
do_proc_dointvec_userhz_jiffies_conv,NULL);
}
@@ -2821,7 +2858,6 @@ int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file
* proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
* @table: the sysctl table
* @write: %TRUE if this is a write to the sysctl file
- * @filp: the file structure
* @buffer: the user buffer
* @lenp: the size of the user buffer
* @ppos: file position
@@ -2834,14 +2870,14 @@ int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file
*
* Returns 0 on success.
*/
-int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
+int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
- return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
+ return do_proc_dointvec(table, write, buffer, lenp, ppos,
do_proc_dointvec_ms_jiffies_conv, NULL);
}
-static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
+static int proc_do_cad_pid(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
struct pid *new_pid;
@@ -2850,7 +2886,7 @@ static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp
tmp = pid_vnr(cad_pid);
- r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
+ r = __do_proc_dointvec(&tmp, table, write, buffer,
lenp, ppos, NULL, NULL);
if (r || !write)
return r;
@@ -2865,50 +2901,49 @@ static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp
#else /* CONFIG_PROC_FS */
-int proc_dostring(struct ctl_table *table, int write, struct file *filp,
+int proc_dostring(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
-int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
+int proc_dointvec(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
-int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
+int proc_dointvec_minmax(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
-int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
+int proc_dointvec_jiffies(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
-int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
+int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
-int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
+int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
-int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
+int proc_doulongvec_minmax(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
}
int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
- struct file *filp,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
diff --git a/kernel/time/Makefile b/kernel/time/Makefile
index 0b0a6366c9d..ee266620b06 100644
--- a/kernel/time/Makefile
+++ b/kernel/time/Makefile
@@ -1,4 +1,4 @@
-obj-y += timekeeping.o ntp.o clocksource.o jiffies.o timer_list.o timecompare.o
+obj-y += timekeeping.o ntp.o clocksource.o jiffies.o timer_list.o timecompare.o timeconv.o
obj-$(CONFIG_GENERIC_CLOCKEVENTS_BUILD) += clockevents.o
obj-$(CONFIG_GENERIC_CLOCKEVENTS) += tick-common.o
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 09113347d32..5e18c6ab2c6 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -394,15 +394,11 @@ void clocksource_resume(void)
{
struct clocksource *cs;
- mutex_lock(&clocksource_mutex);
-
list_for_each_entry(cs, &clocksource_list, list)
if (cs->resume)
cs->resume();
clocksource_resume_watchdog();
-
- mutex_unlock(&clocksource_mutex);
}
/**
diff --git a/kernel/time/timeconv.c b/kernel/time/timeconv.c
new file mode 100644
index 00000000000..86628e755f3
--- /dev/null
+++ b/kernel/time/timeconv.c
@@ -0,0 +1,127 @@
+/*
+ * Copyright (C) 1993, 1994, 1995, 1996, 1997 Free Software Foundation, Inc.
+ * This file is part of the GNU C Library.
+ * Contributed by Paul Eggert (eggert@twinsun.com).
+ *
+ * The GNU C Library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * The GNU C Library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with the GNU C Library; see the file COPYING.LIB. If not,
+ * write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+/*
+ * Converts the calendar time to broken-down time representation
+ * Based on code from glibc-2.6
+ *
+ * 2009-7-14:
+ * Moved from glibc-2.6 to kernel by Zhaolei<zhaolei@cn.fujitsu.com>
+ */
+
+#include <linux/time.h>
+#include <linux/module.h>
+
+/*
+ * Nonzero if YEAR is a leap year (every 4 years,
+ * except every 100th isn't, and every 400th is).
+ */
+static int __isleap(long year)
+{
+ return (year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0);
+}
+
+/* do a mathdiv for long type */
+static long math_div(long a, long b)
+{
+ return a / b - (a % b < 0);
+}
+
+/* How many leap years between y1 and y2, y1 must less or equal to y2 */
+static long leaps_between(long y1, long y2)
+{
+ long leaps1 = math_div(y1 - 1, 4) - math_div(y1 - 1, 100)
+ + math_div(y1 - 1, 400);
+ long leaps2 = math_div(y2 - 1, 4) - math_div(y2 - 1, 100)
+ + math_div(y2 - 1, 400);
+ return leaps2 - leaps1;
+}
+
+/* How many days come before each month (0-12). */
+static const unsigned short __mon_yday[2][13] = {
+ /* Normal years. */
+ {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365},
+ /* Leap years. */
+ {0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366}
+};
+
+#define SECS_PER_HOUR (60 * 60)
+#define SECS_PER_DAY (SECS_PER_HOUR * 24)
+
+/**
+ * time_to_tm - converts the calendar time to local broken-down time
+ *
+ * @totalsecs the number of seconds elapsed since 00:00:00 on January 1, 1970,
+ * Coordinated Universal Time (UTC).
+ * @offset offset seconds adding to totalsecs.
+ * @result pointer to struct tm variable to receive broken-down time
+ */
+void time_to_tm(time_t totalsecs, int offset, struct tm *result)
+{
+ long days, rem, y;
+ const unsigned short *ip;
+
+ days = totalsecs / SECS_PER_DAY;
+ rem = totalsecs % SECS_PER_DAY;
+ rem += offset;
+ while (rem < 0) {
+ rem += SECS_PER_DAY;
+ --days;
+ }
+ while (rem >= SECS_PER_DAY) {
+ rem -= SECS_PER_DAY;
+ ++days;
+ }
+
+ result->tm_hour = rem / SECS_PER_HOUR;
+ rem %= SECS_PER_HOUR;
+ result->tm_min = rem / 60;
+ result->tm_sec = rem % 60;
+
+ /* January 1, 1970 was a Thursday. */
+ result->tm_wday = (4 + days) % 7;
+ if (result->tm_wday < 0)
+ result->tm_wday += 7;
+
+ y = 1970;
+
+ while (days < 0 || days >= (__isleap(y) ? 366 : 365)) {
+ /* Guess a corrected year, assuming 365 days per year. */
+ long yg = y + math_div(days, 365);
+
+ /* Adjust DAYS and Y to match the guessed year. */
+ days -= (yg - y) * 365 + leaps_between(y, yg);
+ y = yg;
+ }
+
+ result->tm_year = y - 1900;
+
+ result->tm_yday = days;
+
+ ip = __mon_yday[__isleap(y)];
+ for (y = 11; days < ip[y]; y--)
+ continue;
+ days -= ip[y];
+
+ result->tm_mon = y;
+ result->tm_mday = days + 1;
+}
+EXPORT_SYMBOL(time_to_tm);
diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c
index fddd69d16e0..1b5b7aa2fdf 100644
--- a/kernel/time/timer_list.c
+++ b/kernel/time/timer_list.c
@@ -275,7 +275,7 @@ static int timer_list_open(struct inode *inode, struct file *filp)
return single_open(filp, timer_list_show, NULL);
}
-static struct file_operations timer_list_fops = {
+static const struct file_operations timer_list_fops = {
.open = timer_list_open,
.read = seq_read,
.llseek = seq_lseek,
diff --git a/kernel/time/timer_stats.c b/kernel/time/timer_stats.c
index 4cde8b9c716..ee5681f8d7e 100644
--- a/kernel/time/timer_stats.c
+++ b/kernel/time/timer_stats.c
@@ -395,7 +395,7 @@ static int tstats_open(struct inode *inode, struct file *filp)
return single_open(filp, tstats_show, NULL);
}
-static struct file_operations tstats_fops = {
+static const struct file_operations tstats_fops = {
.open = tstats_open,
.read = seq_read,
.write = tstats_write,
diff --git a/kernel/timer.c b/kernel/timer.c
index bbb51074680..5db5a8d2681 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -37,7 +37,7 @@
#include <linux/delay.h>
#include <linux/tick.h>
#include <linux/kallsyms.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
#include <linux/sched.h>
#include <asm/uaccess.h>
@@ -46,6 +46,9 @@
#include <asm/timex.h>
#include <asm/io.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/timer.h>
+
u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;
EXPORT_SYMBOL(jiffies_64);
@@ -521,6 +524,25 @@ static inline void debug_timer_activate(struct timer_list *timer) { }
static inline void debug_timer_deactivate(struct timer_list *timer) { }
#endif
+static inline void debug_init(struct timer_list *timer)
+{
+ debug_timer_init(timer);
+ trace_timer_init(timer);
+}
+
+static inline void
+debug_activate(struct timer_list *timer, unsigned long expires)
+{
+ debug_timer_activate(timer);
+ trace_timer_start(timer, expires);
+}
+
+static inline void debug_deactivate(struct timer_list *timer)
+{
+ debug_timer_deactivate(timer);
+ trace_timer_cancel(timer);
+}
+
static void __init_timer(struct timer_list *timer,
const char *name,
struct lock_class_key *key)
@@ -549,7 +571,7 @@ void init_timer_key(struct timer_list *timer,
const char *name,
struct lock_class_key *key)
{
- debug_timer_init(timer);
+ debug_init(timer);
__init_timer(timer, name, key);
}
EXPORT_SYMBOL(init_timer_key);
@@ -568,7 +590,7 @@ static inline void detach_timer(struct timer_list *timer,
{
struct list_head *entry = &timer->entry;
- debug_timer_deactivate(timer);
+ debug_deactivate(timer);
__list_del(entry->prev, entry->next);
if (clear_pending)
@@ -632,7 +654,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires,
goto out_unlock;
}
- debug_timer_activate(timer);
+ debug_activate(timer, expires);
new_base = __get_cpu_var(tvec_bases);
@@ -787,7 +809,7 @@ void add_timer_on(struct timer_list *timer, int cpu)
BUG_ON(timer_pending(timer) || !timer->function);
spin_lock_irqsave(&base->lock, flags);
timer_set_base(timer, base);
- debug_timer_activate(timer);
+ debug_activate(timer, timer->expires);
if (time_before(timer->expires, base->next_timer) &&
!tbase_get_deferrable(timer->base))
base->next_timer = timer->expires;
@@ -1000,7 +1022,9 @@ static inline void __run_timers(struct tvec_base *base)
*/
lock_map_acquire(&lockdep_map);
+ trace_timer_expire_entry(timer);
fn(data);
+ trace_timer_expire_exit(timer);
lock_map_release(&lockdep_map);
@@ -1187,7 +1211,7 @@ static void run_timer_softirq(struct softirq_action *h)
{
struct tvec_base *base = __get_cpu_var(tvec_bases);
- perf_counter_do_pending();
+ perf_event_do_pending();
hrtimer_run_pending();
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index e7163460440..b416512ad17 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -83,7 +83,7 @@ config RING_BUFFER_ALLOW_SWAP
# This allows those options to appear when no other tracer is selected. But the
# options do not appear when something else selects it. We need the two options
# GENERIC_TRACER and TRACING to avoid circular dependencies to accomplish the
-# hidding of the automatic options options.
+# hidding of the automatic options.
config TRACING
bool
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index 844164dca90..26f03ac07c2 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -42,7 +42,6 @@ obj-$(CONFIG_BOOT_TRACER) += trace_boot.o
obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += trace_functions_graph.o
obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o
obj-$(CONFIG_HW_BRANCH_TRACER) += trace_hw_branches.o
-obj-$(CONFIG_POWER_TRACER) += trace_power.o
obj-$(CONFIG_KMEMTRACE) += kmemtrace.o
obj-$(CONFIG_WORKQUEUE_TRACER) += trace_workqueue.o
obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o
@@ -54,5 +53,6 @@ obj-$(CONFIG_EVENT_TRACING) += trace_export.o
obj-$(CONFIG_FTRACE_SYSCALLS) += trace_syscalls.o
obj-$(CONFIG_EVENT_PROFILE) += trace_event_profile.o
obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o
+obj-$(CONFIG_EVENT_TRACING) += power-traces.o
libftrace-y := ftrace.o
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 3eb159c277c..d9d6206e0b1 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -856,6 +856,37 @@ static void blk_add_trace_remap(struct request_queue *q, struct bio *bio,
}
/**
+ * blk_add_trace_rq_remap - Add a trace for a request-remap operation
+ * @q: queue the io is for
+ * @rq: the source request
+ * @dev: target device
+ * @from: source sector
+ *
+ * Description:
+ * Device mapper remaps request to other devices.
+ * Add a trace for that action.
+ *
+ **/
+static void blk_add_trace_rq_remap(struct request_queue *q,
+ struct request *rq, dev_t dev,
+ sector_t from)
+{
+ struct blk_trace *bt = q->blk_trace;
+ struct blk_io_trace_remap r;
+
+ if (likely(!bt))
+ return;
+
+ r.device_from = cpu_to_be32(dev);
+ r.device_to = cpu_to_be32(disk_devt(rq->rq_disk));
+ r.sector_from = cpu_to_be64(from);
+
+ __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq),
+ rq_data_dir(rq), BLK_TA_REMAP, !!rq->errors,
+ sizeof(r), &r);
+}
+
+/**
* blk_add_driver_data - Add binary message with driver-specific data
* @q: queue the io is for
* @rq: io request
@@ -922,10 +953,13 @@ static void blk_register_tracepoints(void)
WARN_ON(ret);
ret = register_trace_block_remap(blk_add_trace_remap);
WARN_ON(ret);
+ ret = register_trace_block_rq_remap(blk_add_trace_rq_remap);
+ WARN_ON(ret);
}
static void blk_unregister_tracepoints(void)
{
+ unregister_trace_block_rq_remap(blk_add_trace_rq_remap);
unregister_trace_block_remap(blk_add_trace_remap);
unregister_trace_block_split(blk_add_trace_split);
unregister_trace_block_unplug_io(blk_add_trace_unplug_io);
@@ -1657,6 +1691,11 @@ int blk_trace_init_sysfs(struct device *dev)
return sysfs_create_group(&dev->kobj, &blk_trace_attr_group);
}
+void blk_trace_remove_sysfs(struct device *dev)
+{
+ sysfs_remove_group(&dev->kobj, &blk_trace_attr_group);
+}
+
#endif /* CONFIG_BLK_DEV_IO_TRACE */
#ifdef CONFIG_EVENT_TRACING
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index cc615f84751..46592feab5a 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1520,7 +1520,7 @@ static int t_show(struct seq_file *m, void *v)
return 0;
}
-static struct seq_operations show_ftrace_seq_ops = {
+static const struct seq_operations show_ftrace_seq_ops = {
.start = t_start,
.next = t_next,
.stop = t_stop,
@@ -1621,8 +1621,10 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
if (!ret) {
struct seq_file *m = file->private_data;
m->private = iter;
- } else
+ } else {
+ trace_parser_put(&iter->parser);
kfree(iter);
+ }
} else
file->private_data = iter;
mutex_unlock(&ftrace_regex_lock);
@@ -2202,7 +2204,7 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
struct trace_parser *parser;
ssize_t ret, read;
- if (!cnt || cnt < 0)
+ if (!cnt)
return 0;
mutex_lock(&ftrace_regex_lock);
@@ -2216,7 +2218,7 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
parser = &iter->parser;
read = trace_get_user(parser, ubuf, cnt, ppos);
- if (trace_parser_loaded(parser) &&
+ if (read >= 0 && trace_parser_loaded(parser) &&
!trace_parser_cont(parser)) {
ret = ftrace_process_regex(parser->buffer,
parser->idx, enable);
@@ -2414,11 +2416,9 @@ unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly;
static void *
__g_next(struct seq_file *m, loff_t *pos)
{
- unsigned long *array = m->private;
-
if (*pos >= ftrace_graph_count)
return NULL;
- return &array[*pos];
+ return &ftrace_graph_funcs[*pos];
}
static void *
@@ -2461,7 +2461,7 @@ static int g_show(struct seq_file *m, void *v)
return 0;
}
-static struct seq_operations ftrace_graph_seq_ops = {
+static const struct seq_operations ftrace_graph_seq_ops = {
.start = g_start,
.next = g_next,
.stop = g_stop,
@@ -2482,16 +2482,10 @@ ftrace_graph_open(struct inode *inode, struct file *file)
ftrace_graph_count = 0;
memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs));
}
+ mutex_unlock(&graph_lock);
- if (file->f_mode & FMODE_READ) {
+ if (file->f_mode & FMODE_READ)
ret = seq_open(file, &ftrace_graph_seq_ops);
- if (!ret) {
- struct seq_file *m = file->private_data;
- m->private = ftrace_graph_funcs;
- }
- } else
- file->private_data = ftrace_graph_funcs;
- mutex_unlock(&graph_lock);
return ret;
}
@@ -2560,9 +2554,7 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
struct trace_parser parser;
- unsigned long *array;
- size_t read = 0;
- ssize_t ret;
+ ssize_t read, ret;
if (!cnt || cnt < 0)
return 0;
@@ -2571,35 +2563,31 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
if (ftrace_graph_count >= FTRACE_GRAPH_MAX_FUNCS) {
ret = -EBUSY;
- goto out;
+ goto out_unlock;
}
- if (file->f_mode & FMODE_READ) {
- struct seq_file *m = file->private_data;
- array = m->private;
- } else
- array = file->private_data;
-
if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) {
ret = -ENOMEM;
- goto out;
+ goto out_unlock;
}
read = trace_get_user(&parser, ubuf, cnt, ppos);
- if (trace_parser_loaded((&parser))) {
+ if (read >= 0 && trace_parser_loaded((&parser))) {
parser.buffer[parser.idx] = 0;
/* we allow only one expression at a time */
- ret = ftrace_set_func(array, &ftrace_graph_count,
+ ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count,
parser.buffer);
if (ret)
- goto out;
+ goto out_free;
}
ret = read;
- out:
+
+out_free:
trace_parser_put(&parser);
+out_unlock:
mutex_unlock(&graph_lock);
return ret;
@@ -3030,7 +3018,7 @@ int unregister_ftrace_function(struct ftrace_ops *ops)
int
ftrace_enable_sysctl(struct ctl_table *table, int write,
- struct file *file, void __user *buffer, size_t *lenp,
+ void __user *buffer, size_t *lenp,
loff_t *ppos)
{
int ret;
@@ -3040,7 +3028,7 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
mutex_lock(&ftrace_lock);
- ret = proc_dointvec(table, write, file, buffer, lenp, ppos);
+ ret = proc_dointvec(table, write, buffer, lenp, ppos);
if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled))
goto out;
diff --git a/kernel/trace/power-traces.c b/kernel/trace/power-traces.c
new file mode 100644
index 00000000000..e06c6e3d56a
--- /dev/null
+++ b/kernel/trace/power-traces.c
@@ -0,0 +1,20 @@
+/*
+ * Power trace points
+ *
+ * Copyright (C) 2009 Arjan van de Ven <arjan@linux.intel.com>
+ */
+
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/power.h>
+
+EXPORT_TRACEPOINT_SYMBOL_GPL(power_start);
+EXPORT_TRACEPOINT_SYMBOL_GPL(power_end);
+EXPORT_TRACEPOINT_SYMBOL_GPL(power_frequency);
+
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 6eef38923b0..d4ff0197054 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -201,8 +201,6 @@ int tracing_is_on(void)
}
EXPORT_SYMBOL_GPL(tracing_is_on);
-#include "trace.h"
-
#define RB_EVNT_HDR_SIZE (offsetof(struct ring_buffer_event, array))
#define RB_ALIGNMENT 4U
#define RB_MAX_SMALL_DATA (RB_ALIGNMENT * RINGBUF_TYPE_DATA_TYPE_LEN_MAX)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index fd52a19dd17..45068269ebb 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -125,13 +125,13 @@ int ftrace_dump_on_oops;
static int tracing_set_tracer(const char *buf);
-#define BOOTUP_TRACER_SIZE 100
-static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata;
+#define MAX_TRACER_SIZE 100
+static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata;
static char *default_bootup_tracer;
static int __init set_ftrace(char *str)
{
- strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE);
+ strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE);
default_bootup_tracer = bootup_tracer_buf;
/* We are using ftrace early, expand it */
ring_buffer_expanded = 1;
@@ -242,13 +242,6 @@ static struct tracer *trace_types __read_mostly;
static struct tracer *current_trace __read_mostly;
/*
- * max_tracer_type_len is used to simplify the allocating of
- * buffers to read userspace tracer names. We keep track of
- * the longest tracer name registered.
- */
-static int max_tracer_type_len;
-
-/*
* trace_types_lock is used to protect the trace_types list.
* This lock is also used to keep user access serialized.
* Accesses from userspace will grab this lock while userspace
@@ -275,12 +268,18 @@ static DEFINE_SPINLOCK(tracing_start_lock);
*/
void trace_wake_up(void)
{
+ int cpu;
+
+ if (trace_flags & TRACE_ITER_BLOCK)
+ return;
/*
* The runqueue_is_locked() can fail, but this is the best we
* have for now:
*/
- if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked())
+ cpu = get_cpu();
+ if (!runqueue_is_locked(cpu))
wake_up(&trace_wait);
+ put_cpu();
}
static int __init set_buf_size(char *str)
@@ -416,7 +415,7 @@ int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
/* read the non-space input */
while (cnt && !isspace(ch)) {
- if (parser->idx < parser->size)
+ if (parser->idx < parser->size - 1)
parser->buffer[parser->idx++] = ch;
else {
ret = -EINVAL;
@@ -619,7 +618,6 @@ __releases(kernel_lock)
__acquires(kernel_lock)
{
struct tracer *t;
- int len;
int ret = 0;
if (!type->name) {
@@ -627,6 +625,11 @@ __acquires(kernel_lock)
return -1;
}
+ if (strlen(type->name) > MAX_TRACER_SIZE) {
+ pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE);
+ return -1;
+ }
+
/*
* When this gets called we hold the BKL which means that
* preemption is disabled. Various trace selftests however
@@ -641,7 +644,7 @@ __acquires(kernel_lock)
for (t = trace_types; t; t = t->next) {
if (strcmp(type->name, t->name) == 0) {
/* already found */
- pr_info("Trace %s already registered\n",
+ pr_info("Tracer %s already registered\n",
type->name);
ret = -1;
goto out;
@@ -692,9 +695,6 @@ __acquires(kernel_lock)
type->next = trace_types;
trace_types = type;
- len = strlen(type->name);
- if (len > max_tracer_type_len)
- max_tracer_type_len = len;
out:
tracing_selftest_running = false;
@@ -703,7 +703,7 @@ __acquires(kernel_lock)
if (ret || !default_bootup_tracer)
goto out_unlock;
- if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE))
+ if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE))
goto out_unlock;
printk(KERN_INFO "Starting tracer '%s'\n", type->name);
@@ -725,14 +725,13 @@ __acquires(kernel_lock)
void unregister_tracer(struct tracer *type)
{
struct tracer **t;
- int len;
mutex_lock(&trace_types_lock);
for (t = &trace_types; *t; t = &(*t)->next) {
if (*t == type)
goto found;
}
- pr_info("Trace %s not registered\n", type->name);
+ pr_info("Tracer %s not registered\n", type->name);
goto out;
found:
@@ -745,17 +744,7 @@ void unregister_tracer(struct tracer *type)
current_trace->stop(&global_trace);
current_trace = &nop_trace;
}
-
- if (strlen(type->name) != max_tracer_type_len)
- goto out;
-
- max_tracer_type_len = 0;
- for (t = &trace_types; *t; t = &(*t)->next) {
- len = strlen((*t)->name);
- if (len > max_tracer_type_len)
- max_tracer_type_len = len;
- }
- out:
+out:
mutex_unlock(&trace_types_lock);
}
@@ -1960,7 +1949,7 @@ static int s_show(struct seq_file *m, void *v)
return 0;
}
-static struct seq_operations tracer_seq_ops = {
+static const struct seq_operations tracer_seq_ops = {
.start = s_start,
.next = s_next,
.stop = s_stop,
@@ -1995,11 +1984,9 @@ __tracing_open(struct inode *inode, struct file *file)
if (current_trace)
*iter->trace = *current_trace;
- if (!alloc_cpumask_var(&iter->started, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL))
goto fail;
- cpumask_clear(iter->started);
-
if (current_trace && current_trace->print_max)
iter->tr = &max_tr;
else
@@ -2174,7 +2161,7 @@ static int t_show(struct seq_file *m, void *v)
return 0;
}
-static struct seq_operations show_traces_seq_ops = {
+static const struct seq_operations show_traces_seq_ops = {
.start = t_start,
.next = t_next,
.stop = t_stop,
@@ -2604,7 +2591,7 @@ static ssize_t
tracing_set_trace_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- char buf[max_tracer_type_len+2];
+ char buf[MAX_TRACER_SIZE+2];
int r;
mutex_lock(&trace_types_lock);
@@ -2754,15 +2741,15 @@ static ssize_t
tracing_set_trace_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- char buf[max_tracer_type_len+1];
+ char buf[MAX_TRACER_SIZE+1];
int i;
size_t ret;
int err;
ret = cnt;
- if (cnt > max_tracer_type_len)
- cnt = max_tracer_type_len;
+ if (cnt > MAX_TRACER_SIZE)
+ cnt = MAX_TRACER_SIZE;
if (copy_from_user(&buf, ubuf, cnt))
return -EFAULT;
@@ -4400,7 +4387,7 @@ __init static int tracer_alloc_buffers(void)
if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL))
goto out_free_buffer_mask;
- if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL))
goto out_free_tracing_cpumask;
/* To save memory, keep the ring buffer size to its minimum */
@@ -4411,7 +4398,6 @@ __init static int tracer_alloc_buffers(void)
cpumask_copy(tracing_buffer_mask, cpu_possible_mask);
cpumask_copy(tracing_cpumask, cpu_all_mask);
- cpumask_clear(tracing_reader_cpumask);
/* TODO: make the number of buffers hot pluggable with CPUS */
global_trace.buffer = ring_buffer_alloc(ring_buf_size,
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 86bcff94791..405cb850b75 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -11,7 +11,6 @@
#include <linux/ftrace.h>
#include <trace/boot.h>
#include <linux/kmemtrace.h>
-#include <trace/power.h>
#include <linux/trace_seq.h>
#include <linux/ftrace_event.h>
@@ -37,7 +36,6 @@ enum trace_type {
TRACE_HW_BRANCHES,
TRACE_KMEM_ALLOC,
TRACE_KMEM_FREE,
- TRACE_POWER,
TRACE_BLK,
__TRACE_LAST_TYPE,
@@ -207,7 +205,6 @@ extern void __ftrace_bad_type(void);
IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
TRACE_GRAPH_RET); \
IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
- IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry, \
TRACE_KMEM_ALLOC); \
IF_ASSIGN(var, ent, struct kmemtrace_free_entry, \
diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
index a431748ddd6..ead3d724599 100644
--- a/kernel/trace/trace_entries.h
+++ b/kernel/trace/trace_entries.h
@@ -330,23 +330,6 @@ FTRACE_ENTRY(hw_branch, hw_branch_entry,
F_printk("from: %llx to: %llx", __entry->from, __entry->to)
);
-FTRACE_ENTRY(power, trace_power,
-
- TRACE_POWER,
-
- F_STRUCT(
- __field_struct( struct power_trace, state_data )
- __field_desc( s64, state_data, stamp )
- __field_desc( s64, state_data, end )
- __field_desc( int, state_data, type )
- __field_desc( int, state_data, state )
- ),
-
- F_printk("%llx->%llx type:%u state:%u",
- __entry->stamp, __entry->end,
- __entry->type, __entry->state)
-);
-
FTRACE_ENTRY(kmem_alloc, kmemtrace_alloc_entry,
TRACE_KMEM_ALLOC,
diff --git a/kernel/trace/trace_event_profile.c b/kernel/trace/trace_event_profile.c
index 55a25c933d1..dd44b876886 100644
--- a/kernel/trace/trace_event_profile.c
+++ b/kernel/trace/trace_event_profile.c
@@ -8,6 +8,57 @@
#include <linux/module.h>
#include "trace.h"
+/*
+ * We can't use a size but a type in alloc_percpu()
+ * So let's create a dummy type that matches the desired size
+ */
+typedef struct {char buf[FTRACE_MAX_PROFILE_SIZE];} profile_buf_t;
+
+char *trace_profile_buf;
+EXPORT_SYMBOL_GPL(trace_profile_buf);
+
+char *trace_profile_buf_nmi;
+EXPORT_SYMBOL_GPL(trace_profile_buf_nmi);
+
+/* Count the events in use (per event id, not per instance) */
+static int total_profile_count;
+
+static int ftrace_profile_enable_event(struct ftrace_event_call *event)
+{
+ char *buf;
+ int ret = -ENOMEM;
+
+ if (atomic_inc_return(&event->profile_count))
+ return 0;
+
+ if (!total_profile_count++) {
+ buf = (char *)alloc_percpu(profile_buf_t);
+ if (!buf)
+ goto fail_buf;
+
+ rcu_assign_pointer(trace_profile_buf, buf);
+
+ buf = (char *)alloc_percpu(profile_buf_t);
+ if (!buf)
+ goto fail_buf_nmi;
+
+ rcu_assign_pointer(trace_profile_buf_nmi, buf);
+ }
+
+ ret = event->profile_enable();
+ if (!ret)
+ return 0;
+
+ kfree(trace_profile_buf_nmi);
+fail_buf_nmi:
+ kfree(trace_profile_buf);
+fail_buf:
+ total_profile_count--;
+ atomic_dec(&event->profile_count);
+
+ return ret;
+}
+
int ftrace_profile_enable(int event_id)
{
struct ftrace_event_call *event;
@@ -17,7 +68,7 @@ int ftrace_profile_enable(int event_id)
list_for_each_entry(event, &ftrace_events, list) {
if (event->id == event_id && event->profile_enable &&
try_module_get(event->mod)) {
- ret = event->profile_enable(event);
+ ret = ftrace_profile_enable_event(event);
break;
}
}
@@ -26,6 +77,33 @@ int ftrace_profile_enable(int event_id)
return ret;
}
+static void ftrace_profile_disable_event(struct ftrace_event_call *event)
+{
+ char *buf, *nmi_buf;
+
+ if (!atomic_add_negative(-1, &event->profile_count))
+ return;
+
+ event->profile_disable();
+
+ if (!--total_profile_count) {
+ buf = trace_profile_buf;
+ rcu_assign_pointer(trace_profile_buf, NULL);
+
+ nmi_buf = trace_profile_buf_nmi;
+ rcu_assign_pointer(trace_profile_buf_nmi, NULL);
+
+ /*
+ * Ensure every events in profiling have finished before
+ * releasing the buffers
+ */
+ synchronize_sched();
+
+ free_percpu(buf);
+ free_percpu(nmi_buf);
+ }
+}
+
void ftrace_profile_disable(int event_id)
{
struct ftrace_event_call *event;
@@ -33,7 +111,7 @@ void ftrace_profile_disable(int event_id)
mutex_lock(&event_mutex);
list_for_each_entry(event, &ftrace_events, list) {
if (event->id == event_id) {
- event->profile_disable(event);
+ ftrace_profile_disable_event(event);
module_put(event->mod);
break;
}
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 56c260b83a9..d128f65778e 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -232,10 +232,9 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
struct trace_parser parser;
- size_t read = 0;
- ssize_t ret;
+ ssize_t read, ret;
- if (!cnt || cnt < 0)
+ if (!cnt)
return 0;
ret = tracing_update_buffers();
@@ -247,7 +246,7 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
read = trace_get_user(&parser, ubuf, cnt, ppos);
- if (trace_parser_loaded((&parser))) {
+ if (read >= 0 && trace_parser_loaded((&parser))) {
int set = 1;
if (*parser.buffer == '!')
@@ -271,42 +270,32 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
static void *
t_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct list_head *list = m->private;
- struct ftrace_event_call *call;
+ struct ftrace_event_call *call = v;
(*pos)++;
- for (;;) {
- if (list == &ftrace_events)
- return NULL;
-
- call = list_entry(list, struct ftrace_event_call, list);
-
+ list_for_each_entry_continue(call, &ftrace_events, list) {
/*
* The ftrace subsystem is for showing formats only.
* They can not be enabled or disabled via the event files.
*/
if (call->regfunc)
- break;
-
- list = list->next;
+ return call;
}
- m->private = list->next;
-
- return call;
+ return NULL;
}
static void *t_start(struct seq_file *m, loff_t *pos)
{
- struct ftrace_event_call *call = NULL;
+ struct ftrace_event_call *call;
loff_t l;
mutex_lock(&event_mutex);
- m->private = ftrace_events.next;
+ call = list_entry(&ftrace_events, struct ftrace_event_call, list);
for (l = 0; l <= *pos; ) {
- call = t_next(m, NULL, &l);
+ call = t_next(m, call, &l);
if (!call)
break;
}
@@ -316,37 +305,28 @@ static void *t_start(struct seq_file *m, loff_t *pos)
static void *
s_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct list_head *list = m->private;
- struct ftrace_event_call *call;
+ struct ftrace_event_call *call = v;
(*pos)++;
- retry:
- if (list == &ftrace_events)
- return NULL;
-
- call = list_entry(list, struct ftrace_event_call, list);
-
- if (!call->enabled) {
- list = list->next;
- goto retry;
+ list_for_each_entry_continue(call, &ftrace_events, list) {
+ if (call->enabled)
+ return call;
}
- m->private = list->next;
-
- return call;
+ return NULL;
}
static void *s_start(struct seq_file *m, loff_t *pos)
{
- struct ftrace_event_call *call = NULL;
+ struct ftrace_event_call *call;
loff_t l;
mutex_lock(&event_mutex);
- m->private = ftrace_events.next;
+ call = list_entry(&ftrace_events, struct ftrace_event_call, list);
for (l = 0; l <= *pos; ) {
- call = s_next(m, NULL, &l);
+ call = s_next(m, call, &l);
if (!call)
break;
}
diff --git a/kernel/trace/trace_hw_branches.c b/kernel/trace/trace_hw_branches.c
index ca7d7c4d0c2..23b63859130 100644
--- a/kernel/trace/trace_hw_branches.c
+++ b/kernel/trace/trace_hw_branches.c
@@ -155,7 +155,7 @@ static enum print_line_t bts_trace_print_line(struct trace_iterator *iter)
seq_print_ip_sym(seq, it->from, symflags) &&
trace_seq_printf(seq, "\n"))
return TRACE_TYPE_HANDLED;
- return TRACE_TYPE_PARTIAL_LINE;;
+ return TRACE_TYPE_PARTIAL_LINE;
}
return TRACE_TYPE_UNHANDLED;
}
diff --git a/kernel/trace/trace_power.c b/kernel/trace/trace_power.c
deleted file mode 100644
index fe1a00f1445..00000000000
--- a/kernel/trace/trace_power.c
+++ /dev/null
@@ -1,218 +0,0 @@
-/*
- * ring buffer based C-state tracer
- *
- * Arjan van de Ven <arjan@linux.intel.com>
- * Copyright (C) 2008 Intel Corporation
- *
- * Much is borrowed from trace_boot.c which is
- * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com>
- *
- */
-
-#include <linux/init.h>
-#include <linux/debugfs.h>
-#include <trace/power.h>
-#include <linux/kallsyms.h>
-#include <linux/module.h>
-
-#include "trace.h"
-#include "trace_output.h"
-
-static struct trace_array *power_trace;
-static int __read_mostly trace_power_enabled;
-
-static void probe_power_start(struct power_trace *it, unsigned int type,
- unsigned int level)
-{
- if (!trace_power_enabled)
- return;
-
- memset(it, 0, sizeof(struct power_trace));
- it->state = level;
- it->type = type;
- it->stamp = ktime_get();
-}
-
-
-static void probe_power_end(struct power_trace *it)
-{
- struct ftrace_event_call *call = &event_power;
- struct ring_buffer_event *event;
- struct ring_buffer *buffer;
- struct trace_power *entry;
- struct trace_array_cpu *data;
- struct trace_array *tr = power_trace;
-
- if (!trace_power_enabled)
- return;
-
- buffer = tr->buffer;
-
- preempt_disable();
- it->end = ktime_get();
- data = tr->data[smp_processor_id()];
-
- event = trace_buffer_lock_reserve(buffer, TRACE_POWER,
- sizeof(*entry), 0, 0);
- if (!event)
- goto out;
- entry = ring_buffer_event_data(event);
- entry->state_data = *it;
- if (!filter_check_discard(call, entry, buffer, event))
- trace_buffer_unlock_commit(buffer, event, 0, 0);
- out:
- preempt_enable();
-}
-
-static void probe_power_mark(struct power_trace *it, unsigned int type,
- unsigned int level)
-{
- struct ftrace_event_call *call = &event_power;
- struct ring_buffer_event *event;
- struct ring_buffer *buffer;
- struct trace_power *entry;
- struct trace_array_cpu *data;
- struct trace_array *tr = power_trace;
-
- if (!trace_power_enabled)
- return;
-
- buffer = tr->buffer;
-
- memset(it, 0, sizeof(struct power_trace));
- it->state = level;
- it->type = type;
- it->stamp = ktime_get();
- preempt_disable();
- it->end = it->stamp;
- data = tr->data[smp_processor_id()];
-
- event = trace_buffer_lock_reserve(buffer, TRACE_POWER,
- sizeof(*entry), 0, 0);
- if (!event)
- goto out;
- entry = ring_buffer_event_data(event);
- entry->state_data = *it;
- if (!filter_check_discard(call, entry, buffer, event))
- trace_buffer_unlock_commit(buffer, event, 0, 0);
- out:
- preempt_enable();
-}
-
-static int tracing_power_register(void)
-{
- int ret;
-
- ret = register_trace_power_start(probe_power_start);
- if (ret) {
- pr_info("power trace: Couldn't activate tracepoint"
- " probe to trace_power_start\n");
- return ret;
- }
- ret = register_trace_power_end(probe_power_end);
- if (ret) {
- pr_info("power trace: Couldn't activate tracepoint"
- " probe to trace_power_end\n");
- goto fail_start;
- }
- ret = register_trace_power_mark(probe_power_mark);
- if (ret) {
- pr_info("power trace: Couldn't activate tracepoint"
- " probe to trace_power_mark\n");
- goto fail_end;
- }
- return ret;
-fail_end:
- unregister_trace_power_end(probe_power_end);
-fail_start:
- unregister_trace_power_start(probe_power_start);
- return ret;
-}
-
-static void start_power_trace(struct trace_array *tr)
-{
- trace_power_enabled = 1;
-}
-
-static void stop_power_trace(struct trace_array *tr)
-{
- trace_power_enabled = 0;
-}
-
-static void power_trace_reset(struct trace_array *tr)
-{
- trace_power_enabled = 0;
- unregister_trace_power_start(probe_power_start);
- unregister_trace_power_end(probe_power_end);
- unregister_trace_power_mark(probe_power_mark);
-}
-
-
-static int power_trace_init(struct trace_array *tr)
-{
- power_trace = tr;
-
- trace_power_enabled = 1;
- tracing_power_register();
-
- tracing_reset_online_cpus(tr);
- return 0;
-}
-
-static enum print_line_t power_print_line(struct trace_iterator *iter)
-{
- int ret = 0;
- struct trace_entry *entry = iter->ent;
- struct trace_power *field ;
- struct power_trace *it;
- struct trace_seq *s = &iter->seq;
- struct timespec stamp;
- struct timespec duration;
-
- trace_assign_type(field, entry);
- it = &field->state_data;
- stamp = ktime_to_timespec(it->stamp);
- duration = ktime_to_timespec(ktime_sub(it->end, it->stamp));
-
- if (entry->type == TRACE_POWER) {
- if (it->type == POWER_CSTATE)
- ret = trace_seq_printf(s, "[%5ld.%09ld] CSTATE: Going to C%i on cpu %i for %ld.%09ld\n",
- stamp.tv_sec,
- stamp.tv_nsec,
- it->state, iter->cpu,
- duration.tv_sec,
- duration.tv_nsec);
- if (it->type == POWER_PSTATE)
- ret = trace_seq_printf(s, "[%5ld.%09ld] PSTATE: Going to P%i on cpu %i\n",
- stamp.tv_sec,
- stamp.tv_nsec,
- it->state, iter->cpu);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- return TRACE_TYPE_HANDLED;
- }
- return TRACE_TYPE_UNHANDLED;
-}
-
-static void power_print_header(struct seq_file *s)
-{
- seq_puts(s, "# TIMESTAMP STATE EVENT\n");
- seq_puts(s, "# | | |\n");
-}
-
-static struct tracer power_tracer __read_mostly =
-{
- .name = "power",
- .init = power_trace_init,
- .start = start_power_trace,
- .stop = stop_power_trace,
- .reset = power_trace_reset,
- .print_line = power_print_line,
- .print_header = power_print_header,
-};
-
-static int init_power_trace(void)
-{
- return register_tracer(&power_tracer);
-}
-device_initcall(init_power_trace);
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
index 687699d365a..2547d8813cf 100644
--- a/kernel/trace/trace_printk.c
+++ b/kernel/trace/trace_printk.c
@@ -11,7 +11,6 @@
#include <linux/ftrace.h>
#include <linux/string.h>
#include <linux/module.h>
-#include <linux/marker.h>
#include <linux/mutex.h>
#include <linux/ctype.h>
#include <linux/list.h>
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 0f6facb050a..8504ac71e4e 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -296,14 +296,14 @@ static const struct file_operations stack_trace_fops = {
int
stack_trace_sysctl(struct ctl_table *table, int write,
- struct file *file, void __user *buffer, size_t *lenp,
+ void __user *buffer, size_t *lenp,
loff_t *ppos)
{
int ret;
mutex_lock(&stack_sysctl_mutex);
- ret = proc_dointvec(table, write, file, buffer, lenp, ppos);
+ ret = proc_dointvec(table, write, buffer, lenp, ppos);
if (ret || !write ||
(last_stack_tracer_enabled == !!stack_tracer_enabled))
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 8712ce3c6a0..9fbce6c9d2e 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -2,7 +2,7 @@
#include <trace/events/syscalls.h>
#include <linux/kernel.h>
#include <linux/ftrace.h>
-#include <linux/perf_counter.h>
+#include <linux/perf_event.h>
#include <asm/syscall.h>
#include "trace_output.h"
@@ -384,10 +384,13 @@ static int sys_prof_refcount_exit;
static void prof_syscall_enter(struct pt_regs *regs, long id)
{
- struct syscall_trace_enter *rec;
struct syscall_metadata *sys_data;
+ struct syscall_trace_enter *rec;
+ unsigned long flags;
+ char *raw_data;
int syscall_nr;
int size;
+ int cpu;
syscall_nr = syscall_get_nr(current, regs);
if (!test_bit(syscall_nr, enabled_prof_enter_syscalls))
@@ -402,20 +405,38 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
size = ALIGN(size + sizeof(u32), sizeof(u64));
size -= sizeof(u32);
- do {
- char raw_data[size];
+ if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE,
+ "profile buffer not large enough"))
+ return;
+
+ /* Protect the per cpu buffer, begin the rcu read side */
+ local_irq_save(flags);
- /* zero the dead bytes from align to not leak stack to user */
- *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
+ cpu = smp_processor_id();
+
+ if (in_nmi())
+ raw_data = rcu_dereference(trace_profile_buf_nmi);
+ else
+ raw_data = rcu_dereference(trace_profile_buf);
+
+ if (!raw_data)
+ goto end;
- rec = (struct syscall_trace_enter *) raw_data;
- tracing_generic_entry_update(&rec->ent, 0, 0);
- rec->ent.type = sys_data->enter_id;
- rec->nr = syscall_nr;
- syscall_get_arguments(current, regs, 0, sys_data->nb_args,
- (unsigned long *)&rec->args);
- perf_tpcounter_event(sys_data->enter_id, 0, 1, rec, size);
- } while(0);
+ raw_data = per_cpu_ptr(raw_data, cpu);
+
+ /* zero the dead bytes from align to not leak stack to user */
+ *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
+
+ rec = (struct syscall_trace_enter *) raw_data;
+ tracing_generic_entry_update(&rec->ent, 0, 0);
+ rec->ent.type = sys_data->enter_id;
+ rec->nr = syscall_nr;
+ syscall_get_arguments(current, regs, 0, sys_data->nb_args,
+ (unsigned long *)&rec->args);
+ perf_tp_event(sys_data->enter_id, 0, 1, rec, size);
+
+end:
+ local_irq_restore(flags);
}
int reg_prof_syscall_enter(char *name)
@@ -460,8 +481,12 @@ void unreg_prof_syscall_enter(char *name)
static void prof_syscall_exit(struct pt_regs *regs, long ret)
{
struct syscall_metadata *sys_data;
- struct syscall_trace_exit rec;
+ struct syscall_trace_exit *rec;
+ unsigned long flags;
int syscall_nr;
+ char *raw_data;
+ int size;
+ int cpu;
syscall_nr = syscall_get_nr(current, regs);
if (!test_bit(syscall_nr, enabled_prof_exit_syscalls))
@@ -471,12 +496,46 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
if (!sys_data)
return;
- tracing_generic_entry_update(&rec.ent, 0, 0);
- rec.ent.type = sys_data->exit_id;
- rec.nr = syscall_nr;
- rec.ret = syscall_get_return_value(current, regs);
+ /* We can probably do that at build time */
+ size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64));
+ size -= sizeof(u32);
- perf_tpcounter_event(sys_data->exit_id, 0, 1, &rec, sizeof(rec));
+ /*
+ * Impossible, but be paranoid with the future
+ * How to put this check outside runtime?
+ */
+ if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE,
+ "exit event has grown above profile buffer size"))
+ return;
+
+ /* Protect the per cpu buffer, begin the rcu read side */
+ local_irq_save(flags);
+ cpu = smp_processor_id();
+
+ if (in_nmi())
+ raw_data = rcu_dereference(trace_profile_buf_nmi);
+ else
+ raw_data = rcu_dereference(trace_profile_buf);
+
+ if (!raw_data)
+ goto end;
+
+ raw_data = per_cpu_ptr(raw_data, cpu);
+
+ /* zero the dead bytes from align to not leak stack to user */
+ *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
+
+ rec = (struct syscall_trace_exit *)raw_data;
+
+ tracing_generic_entry_update(&rec->ent, 0, 0);
+ rec->ent.type = sys_data->exit_id;
+ rec->nr = syscall_nr;
+ rec->ret = syscall_get_return_value(current, regs);
+
+ perf_tp_event(sys_data->exit_id, 0, 1, rec, size);
+
+end:
+ local_irq_restore(flags);
}
int reg_prof_syscall_exit(char *name)
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index 9489a0a9b1b..cc89be5bc0f 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -48,7 +48,7 @@ static struct hlist_head tracepoint_table[TRACEPOINT_TABLE_SIZE];
/*
* Note about RCU :
- * It is used to to delay the free of multiple probes array until a quiescent
+ * It is used to delay the free of multiple probes array until a quiescent
* state is reached.
* Tracepoint entries modifications are protected by the tracepoints_mutex.
*/
diff --git a/kernel/uid16.c b/kernel/uid16.c
index 0314501688b..419209893d8 100644
--- a/kernel/uid16.c
+++ b/kernel/uid16.c
@@ -4,7 +4,6 @@
*/
#include <linux/mm.h>
-#include <linux/utsname.h>
#include <linux/mman.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
diff --git a/kernel/utsname_sysctl.c b/kernel/utsname_sysctl.c
index 92359cc747a..69eae358a72 100644
--- a/kernel/utsname_sysctl.c
+++ b/kernel/utsname_sysctl.c
@@ -42,14 +42,14 @@ static void put_uts(ctl_table *table, int write, void *which)
* Special case of dostring for the UTS structure. This has locks
* to observe. Should this be in kernel/sys.c ????
*/
-static int proc_do_uts_string(ctl_table *table, int write, struct file *filp,
+static int proc_do_uts_string(ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
struct ctl_table uts_table;
int r;
memcpy(&uts_table, table, sizeof(uts_table));
uts_table.data = get_uts(table, write);
- r = proc_dostring(&uts_table,write,filp,buffer,lenp, ppos);
+ r = proc_dostring(&uts_table,write,buffer,lenp, ppos);
put_uts(table, write, uts_table.data);
return r;
}